### Interference

Quite a lot of combinations seems to consist of short sequences. Somewhere, these sequences interfere with each other. It is necessary to see both the sequences and the interferences.

 Black to move

4bnk1/6p1/6qp/PN1pPp2/5P2/5N2/3Q3K/8 b - - 1 1

[solution]

First sequence:

1. . . . Bxb5
LPDO: the knight drops off

Second sequence:

2.Qxd5+ Ne6 3.Qxb5
Double attack: on both black's King and Bishop on b5
Both sequences 1 and 2 interfere at b5

Third sequence:

3. . . . Qh5+ 4.Kg2 Qxf3 5.Kxf3

Double attack: on King and Knight.

Fourth sequence:

5. . . . Nd4 6.Ke3 Nxb5

Fourth sequence interferes with sequences 2 and 3 at b5 and f3

In an Xmind scheme:

This gives an idea what you must achieve in the realm of visual perception. In order to find the move 2. . . . Ne6 you must already see the knight fork in the fourth sequence.

1. My apology if this question comes off as being pedantic; I do not intend that.

Would it be more descriptive to use "intersect" rather than "interfere"? Intersect seems to be what I'm seeing in this example, since each sequence seems to intersect with (and facilitate) the next sequence, ultimately tying the overall sequence together.

This position is an instance of perception of edges (boundaries) - between one sequence and the next consecutive sequence.

Edges denote connections between two different things; in this case, the "boundaries" are between the sequences. It's fairly easy to "SEE" each individual sequence in isolation. The "glue" connecting the sequences are (in essence) stepping stone positions.

I think 2… Ne6 is an example of what GM Valeri Beim described as a "resulting" move. It is the "result" of calculating various sequences ahead, and then discovering moves that are useful (or even essential) for making the entire sequence workable.

1. Intersection is fine with me. We already use interference for another tactical theme. So I already was in doubt.

2. The reason for this post is twofold. I want somehow to simplify matters. By splitting the combination into sequences with separate themes, and intersections. Since system 2 is at its best with simple straight sequences.

The second point is to get an idea what salient points are there which system 1 must learn to see. On the one hand there are the tactical themes like double attack, discovered attack, pin, B.A.D. (Barely Adequate Defended) pieces et cetera, and on the other hand there are the intersection points. Where one sequence interacts with the other. You can only find Ne6 when you are aware of the royal fork on d4

The question is, if system 1 learns by copying examples, is just this kind of analysis as in the post enough?

3. PART I:

I am of two “minds” (imagine that!) regarding the sequences in this problem and what we should visually perceive in this position.

I don’t think in terms of “sequences” per se, any more than I think like a tree. I can readily “SEE” them, but don’t consider them to be an important part of visual perception. It seems (to me) to be purely descriptive rather than prescriptive. Visual perspective is simply “SEEing” what is there (the parts) and the over-arching result (the whole) that makes “sense” of the parts when combined.

There are several “parts” of interest. Obviously (perhaps), the WNb5 is hanging [LPDO; 0:1]. If we just note that, we can continue to “SEE” what other interesting facts we can discern just by scanning the surface “clues.” It is very important to NOT jump into the first mental “straight jacket” we “SEE.” [Recall the anecdote of the drunk looking for his keys.]

WNb5 is LPDO [0:1]. It takes a split second to become aware of that fact. Likewise, it take another split second to “SEE” that following this capture, White [having the right to move first] can regain his piece by capturing on d5 WITH CHECK, and then recapturing on the b5-square. So, White can restore the material balance; that much seems intuitively obvious. So the initial sequence (to me) is 1… Bxb5 2. Qxd5+ [some move] 3. Qxb5.

What is NOT intuitively obvious is WHY Black should move the Knight to e6 rather than either moving the Black King out of check to a safer square OR why Black should not interpose the Black Queen on e6 [2… Qe6].

Looking at the resulting position, it is obvious that White has two trump cards: an outside passed pawn [a5] AND a protected passed pawn [e5]. The White Queen also may prove to be somewhat off-side from his King, which might be significant because Black’s Queen is in a position to attack the White King. By moving the Black Knight to e6, Black is doing two things at once: blockading the d5 passed pawn AND moving the Knight closer to stopping the a5 outside passed pawn. As Nimzovich put it, the blockader is rewarded by gaining a broader range of action without being inhibited in any way. The pin on the Black Knight is temporary, because White intends to recapture on b5. Virtue is its own reward!

After 1… Bxb5 2. Qxd5+ Ne6 (unforced but logical) 3. Qxd5, Black now has the right to move first. Time for a stepping stone position!

4. PART II:

The focus now shifts (or at least, SHOULD shift) to any possibilities for Black to gain an advantage. We must PERCEIVE the potential fork of two White pieces on d4 by that brave blockader on e6! Make that guy do multiple things. There is a visual “clue” in that the BNe6 is sitting on the same color square as the WQb5 and WNf3. System 2 evaluates that fork possibility and concludes that it does NOT work because d4 is now merely B.A.D. [1:1]. But we KNOW (right?!?) that when trying to take advantage of a B.A.D. square, one of the first things to “LOOK” at is some way to remove a defender of it or add another attacker to it with tempo. Since the WNf3 is the only defender, it is natural to look for some way to eliminate it or divert it away from the square.

In this case, since we “SEE” a potential for a fork on d4, we need to accomplish two things: remove the WNf3 as a defender (simply because it IS a defender) AND substitute a different piece that allows us to fork the White Queen and that replacement piece. [Nimzovich’s maxim Changez les blockeurs! is applicable to “blockaders” of our plan to set up a fork just as much as it is to blockaders of pawns!] The only “candidate” replacement piece is the White King. System 2 must redirect its focus toward getting the White King to the f3-square. This can be accomplished by a series of CHECKS while simultaneously attacking the WNf3. WE HAVE A PLAN! System 1, work your magic and figure out how to accomplish this sub-goal!

System 1 can “SEE” that checks will immediately or eventually drive the White King into defense of the f3-square. When/if that occurs, Black can capture WNf3 WITH CHECK, forcing the White King to recapture, setting up the desire fork on the d4-square. Otherwise, if White tries to avoid capturing on the f-square at all costs, it WILL cost him the WNf3 anyway. Black must always proceed using checks, to avoid giving White the opportunity to move the White Queen out of range of the potential fork. White will try to avoid all situations where the f3-capture occurs; he can delay it but not prevent it.

I found out after-the-fact (using Chess Tempo to analyze the position), that White can avoid the fork on the d4-square by simply NOT recapturing on the b5-square, ending up a piece down. GM Stockfish “thinks” there are 5 (!!!) viable alternatives that are better than recapturing immediately on the b5-square! Those alternatives did NOT come up from MY System 1!!

Perhaps you can find something “nourishing” for your current line of investigation in that verbose “word salad.”

5. lichess-org Puzzle #EnGvs

From game 3+0 • Blitz
Ismailrekikoss (2420)
chessfootbal (2402)

FEN: 1r4k1/1p3p2/1Np3pp/p1P1P2q/5Pn1/P2Q2P1/1P4K1/7R b - - 4 34

A much simpler example of the IDEA of capturing a B.A.D. piece [1:1] defended by the King, forcing the King to step onto a mined square for a Knight fork. The surface-level clue: the Black Knight is sitting on the same color square as the h1-square and d3-square. White’s previous move was 34. R(d1)h1, “attacking” the Black Queen and (obviously) overlooking that he was creating a B.A.D. square. Even fairly strong players can make simple oversights when in severe time pressure.

6. FEN: 3r4/1p1rnqpk/2p3b1/4ppPp/p2PP2P/P3BP2/1P2B1Q1/2RR2K1 w - - 0 1

Chess Tempo Puzzle #158687778

Tristan, Leonardo (2535) vs Jobava, Baadur (2603)

White just played 34. d4xe5. The d-file LoA is opened for both players. The d7-square is B.A.D. [1:1]. The d1-square is B.A.D. [2:2] The WBe3 is LPDO. Black has the right to move first.

What connects those facts?

Black cannot remove either defender of the d1-square, so it follows that he must “SEE” if he can add an attacker with tempo. The Black Queen is the only potential attacker not currently in use against the d1-square. Simultaneously, the Black Queen can attack the WBe3, creating a double attack on e3 and d1 with 34… Qb3.

White can attempt to escape by capturing on d7 with the intermezzo/counter-threat 35. Rxd7. Unfortunately, Black has a Zwischenschach 35… Qxe3+ 36. Kh2 Rxd7.

White cannot escape material loss.

The game continuation was 34. dxe5 Qb3 35. Rd3 Rxd3 36. Bxd3 Rxd3 37. Bc5 Rxf3 38. Rc2 Rg3 White resigns.

7. FEN: 2r5/3qk3/p2p1p1r/1p1Bp1b1/1P1pP3/P2P1Q2/1KP2P2/5RR1 w - - 6 34

The f7-square is B.A.D. [1:1]. The BRh6 is potentially LPDO, defended solely by BBg5.

What connects the two potential targets?

Removal of BBg5 by 34. Rxg5 simultaneously opens access to the f7-square AND removes the defender of BRh6. The BPf6 is (in essence) pinned, overloaded with two duties: protecting the BBg5 AND preventing the White Queen from getting to the f7-square. After 2… fxg6 3. Qf7+ Kd8, the f8-square then becomes the focal point for a fork: 4. Qf8+ Kc7 5. Qxh6 ending up a Bishop ahead. The Zwischenschach on f7 sets up the subsequent fork.

It is important to “SEE” the potential LoAs of the White Queen as well as the various Functions of the pieces and squares. This illustrates the concept of “SEEing” through intervening and interfering pieces to potentially accessible squares.

8. This comment has been removed by the author.

9. Out of curiosity at how much I did NOT “SEE” in this post’s position (given above), on Chess Tempo I played the moves 1... Bxb5 2. Qxd5+ Ne6 and let GM Stockfish “look” at the best 10 alternatives for 24(!) hours. Here are the results. I WAS “surprised” to find 3.Qxb5 Qh5+ in 9th(!) place. I intuited that White might have “some chances” with an advanced outside passed pawn, with his Queen near that pawn, and the Black pieces all over on the other side of the board. However, human intuition cannot match looking ahead 14408.28 MILLION nodes.

1. D45 -5.75 3.Nh4 Qe8 4.Nxf5 Kh7 5.Qf3 Qd8 6.Nd6 Qh4+ 7.Kg1 Qe1+ 8.Kh2 Qd2+ 9.Kg3 Bd3 10.Qf2 Qxa5 11.Kh3 Qd5 12.Kh2 Nd4 13.Qg2 Qxg2+ 14.Kxg2 Kg6 15.Ne8 Be4+ 16.Kg1 Bc6 17.Nd6 Ne2+ 18.Kf2 Nxf4 19.Kg3 Ne6 20.Nc8 Bb7 21.Nd6 Ba6 22.Kf3 h5 23.Ke3

2. D45 -7.69 3.Ne1 Qe8 4.Kg3 Kh7 5.Qb3 Bc6 6.Kf2 Qe7 7.Qe3 Qh4+ 8.Qg3 Qh1 9.a6 Nc5 10.Ke2 Bb5+ 11.Kd1 Qe4 12.Kc1 Bxa6 13.Qf2 Ne6 14.Nc2 Bd3 15.Ne3 Nxf4 16.e6 Nxe6 17.Kd2 f4 18.Ng4 Qc4 19.Ne5

3. D45 -8.03 3.Ng1 Qe8 4.a6 Bxa6 5.Kg3 Kh7 6.Nh3 Qf7 7.Qd1 Qg6+ 8.Kf2 Bb7 9.Qg1 Qh5 10.Qg3 Qd1 11.Qe3 Qh1 12.Qg3 Qe4 13.Qe3 Qg2+ 14.Ke1 Bf3 15.Ng1 Bg4 16.Qf2 Qe4+ 17.Kd2 Nxf4 18.Qg3 Qd4+ 19.Ke1 Qxe5+ 20.Kf2

4. D45 -9.35 3.a6 Bxa6 4.Nh4 Qe8 5.Qf3 Qa4 6.Qf2 Qe4 7.Qf3 Bb7 8.Qxe4 Bxe4 9.Ng6 Kh7 10.Ne7 Nxf4 11.Nc8 h5 12.Kg1 g5 13.Na7 h4 14.Kf1 Kg6 15.Nc8 g4 16.Kf2 Nd3+ 17.Ke3 Nxe5 18.Nd6 g3 19.Kd2 Nd3 20.Kc3 h3 21.Kb3 g2 22.Nb5 h2 23.Kc2 Nf2+ 24.Kb2

5. D45 -31.74 3.Kh1 Qe8 4.Kg2 Kh7 5.Qd2 Qh5 6.Kf2 Bc6 7.Qe3 Qg4 8.Nd4 Qh4+ 9.Ke2 Nxf4+ 10.Kd2 Qh2+ 11.Kd1 Qh1+ 12.Qe1 Ba4+ 13.Kd2 Qd5 14.Qa1 Qxa5+ 15.Qc3 Qd5 16.Ke1 Qxe5+ 17.Kd2 Qd5 18.Ke3 Qe4+ 19.Kd2 Qg2+ 20.Kc1 Ne2+ 21.Nxe2 Qxe2 22.Qc5 Qc2+ 23.Qxc2 Bxc2 24.Kxc2 Kg6 25.Kd3 f4 26.Ke4 Kg5 27.Kd5 f3 28.Kc4 Kg6 29.Kd3 f2 30.Ke2 f1=Q+ 31.Kxf1 Kf6 32.Kf2

6. D45 -31.74 3.Qb3 Bc6 4.Nh4 Qf7 5.Kg3 Kh7 6.Kf2 Be4 7.Nf3 Bxf3 8.Qxf3 Qa7+ 9.Qe3 Qxa5 10.Qd3 Qa7+ 11.Kf3 Qb7+ 12.Kf2 Qb2+ 13.Kf3 Qg2+ 14.Kxg2 Nxf4+ 15.Kf3 Nxd3 16.e6 Kg6 17.e7 Kf7 18.e8=Q+ Kxe8 19.Ke3 Nc5 20.Kf4 Ne6+ 21.Kxf5 Ke7 22.Ke5 Kf7 23.Kd6 Kg6 24.Ke5 Nc7 25.Kd6 Kh7 26.Ke7 Ne6 27.Kxe6 g5 28.Kf5 Kg7 29.Ke6 Kg6 30.Ke5 Kh5 31.Ke4 g4 32.Kf4

7. D45 -33.90 3.Qa2 Kh7 4.Qg2 Qh5+ 5.Qh3 Qxh3+ 6.Kxh3 Nxf4+ 7.Kg3 Ne6 8.Kf2 g5 9.Ne1 f4 10.Nc2 Bc6 11.Nb4 Bb7 12.a6 Ba8 13.Nd3 h5 14.Nb2 g4 15.Nc4 g3+ 16.Kf1 f3 17.Nb6 Bc6 18.a7 Bb5+ 19.Ke1 f2+ 20.Kd2 f1=Q 21.a8=Q Qe2+ 22.Kc1 Qe1+ 23.Kb2 Qxe5+ 24.Kc2 Qc5+ 25.Kd2 Qd4+ 26.Kc1 Qe3+ 27.Kd1 Qe2+ 28.Kc1 Qe1+ 29.Kb2

8. D44 -37.18 3.Qb7 Bd3 4.Qb3 Be4 5.Nh4 Qe8 6.Kg3 Kh7 7.Qb6 Qd7 8.Qe3 Qd1 9.Nf3 Bxf3 10.Qxf3 Qe1+ 11.Kh2 Qd2+ 12.Qg2 Qxf4+ 13.Kh1 Qh4+ 14.Kg1 Qd4+ 15.Qf2 Qxf2+ 16.Kxf2 Nc7 17.Kg3 g5 18.Kf3 Kg7 19.Ke3 Kg6 20.Kd4 Kf7 21.Kc3 Ke6 22.Kc4 Kxe5 23.Kc5 g4 24.a6 Nxa6+ 25.Kc6 g3 26.Kb7 g2 27.Kxa6 g1=Q 28.Kb5 Qg2

9. D44 -37.85 3.Qxb5 Qh5+ 4.Kg1 Qg4+ 5.Kf2 Qxf3+ 6.Ke1 Qe4+ 7.Kd1 Kh7 8.a6 Nc7 9.Qa5 Qd3+ 10.Kc1 Qc4+ 11.Kb2 Nxa6 12.Qc3 Qxc3+ 13.Kxc3 Nc5 14.Kd4 Ne6+ 15.Ke3 g5 16.fxg5 hxg5 17.Kd3 Kg6 18.Kc4 Nd8 19.Kc5 g4 20.Kd4 Kf7 21.Ke3 Ke6 22.Kf2 Nc6 23.Kg3 Kxe5 24.Kh4 f4 25.Kxg4 Ke4 26.Kg5 f3 27.Kh6 f2 28.Kg6 f1=Q 29.Kh7 Ke5 30.Kg8

10. D44 -39.60 3.Ng5 hxg5 4.Qxb5 Qh5+ 5.Kg1 Qg4+ 6.Kh2 Qxf4+ 7.Kg2 Qd2+ 8.Kf1 Qc1+ 9.Kf2 Qc5+ 10.Qxc5 Nxc5 11.Ke3 Kf7 12.Kd4 Nb3+ 13.Kd5 Nxa5 14.Kd6 g4 15.Kd7 Nc6 16.e6+ Kf6 17.Kd6 g3 18.Kd7 g2 19.e7 Nxe7 20.Kc7 Ke6 21.Kb8 g1=Q 22.Kb7 f4 23.Ka8 f3 24.Kb8

1. Interesting. And intimidating

10. Sorry, this is gonna be LONG.

PART I:

I just re-read Edwards’ Chapter 5: Drawing on Your Childhood Artistry. It is quite interesting to “SEE” the various stages that we go through from infancy to adulthood in connection to drawing. [I believe similar stages occur in every skill INCLUDING CHESS for every person.] While studying her description (again), I was “struck” with an insight that had never occurred to me. WE ARE STUCK IN VERBAL MODE! We are unaware of this state (and its limitations) like a fish is unaware of living in water. (“SEE” that analogy in your mind’s eye.)

I will use a well-known poem as an example.

The Blind Men and the Elephant
A poem by John Godfrey Saxe (1816–1887) (Based upon a Hindu Parable)

It was six men of Indostan To learning much inclined,
Who went to see the Elephant (Though all of them were blind),
That each by observation Might satisfy his mind.

The First approached the Elephant, And happening to fall
Against his broad and sturdy side, At once began to bawl:
"God bless me! but the Elephant Is very like a wall!"

The Second, feeling of the tusk, Cried, "Ho! What have we here?
So very round and smooth and sharp? To me 'tis mighty clear
This wonder of an Elephant Is very like a spear!"

The Third approached the animal, And happening to take
The squirming trunk within his hands, Thus boldly up and spake:
"I see," quoth he, "the Elephant Is very like a snake!"

The Fourth reached out an eager hand, And felt about the knee.
"What most this wondrous beast is like Is mighty plain," quoth he;
"'Tis clear enough the Elephant Is very like a tree!"

The Fifth who chanced to touch the ear, Said: "E'en the blindest man
Can tell what this resembles most; Deny the fact who can,
This marvel of an Elephant Is very like a fan!"

Than, seizing on the swinging tail That fell within his scope,
"I see," quoth he, "the Elephant Is very like a rope!”

And so these men of Indostan Disputed loud and long,
Each in his own opinion Exceeding stiff and strong,
Though each was partly in the right And all were in the wrong!

So oft in theologic [adult chess improvement] wars The disputants, I ween,
Rail on in utter ignorance Of what each other mean,
And prate about an Elephant Not one of them has seen!

Note the linear sequential step-by-step nature of telling the story IN WORDS. Note the effort it takes to figure out what’s important (the IDEA) conveyed by all those words. It is not a “natural” limitation of adults to focus on WORDS; it is LEARNED behavior to bypass or ignore visual perception, and it occurs at an early age. We RELY on verbal descriptions to communicate with each other. (I’m doing THAT here!)

11. PART II:

I can’t put a picture into a comment (or maybe it can be done, but I don’t know how to do it). So, follow this link to a picture associated with this story:

A picture worth a thousand words!

There are NO WORDS in the picture (there ARE pictures of this story with words), and yet you can “SEE” the WHOLE story in a glance. If you choose to focus on any aspect of it, you can “drill down” to each individual observation. This is the fractal nature of the picture. The WHOLE is mirrored in its PARTS.

THIS is an illustration of visual perception vice verbalization. THIS is what children DO that adults have such difficulty doing! Why? Because we approach acquisition of the whole picture VERBALLY, through WORDS, and bypass or ignore “SEEing” holistically. As a consequence, it is only through great effort that we can (sometimes) toss the “word salad” and make something edible out of it.

12. PART III:

Children in the earlier stages of learning go DIRECTLY to the WHOLE picture WORDLESSLY. They do not even attempt to verbalize, categorize, abstract or any other activity based on words; they just “SEE”!

THIS IS THE PRODIGY “TRICK”!

This is how Capablanca learned chess at such an early age. He watched good players DO chess. He didn’t mindlessly copy them but PERCEIVED and CONCEPTUALIZED – WITHOUT WORDS. One of his greatest “insights” (learned without verbal instruction) is passed along VISUALLY as well as verbally in his book The Chess Legacy of José Raoul Capablanca: Last Lectures, pg. 23 using pawn endings as illustrations.

In a position in which White has one pawn [b2] against two Black pawns [a6,b5] on the far side of the board, Capablanca gives the following advice:

“But let us suppose that White moves first [the right to move first]; in that event he wins by playing 1. b4, and here we have one of the most important fundamental principles of chess. Perhaps the most important of all, to wit: Advance the Pawn which retrains two Pawns. This principle can be more broadly expressed in the following general form: apply a unit of force which restrains anther force of greater strength.

He “SAW” this demonstrated while he was a child, watching his father PLAY chess! His father MAY have verbalized this “principle” explicitly at some point, but I doubt it.

When I was training in martial arts, the instruction was usually non-verbal. The instructor would demonstrate a technique or movement, and then the student had to try to duplicate it. If there was a problem, the instructor would simply move the appropriate limb or the body through the correct movement, often with no verbalization. Initially, it was frustrating for me because I (at 40+ years of age) wanted a VERBAL description of what to do so I could go back to the verbal description whenever needed to refresh my memory or investigate subtleties.

One time, I was “practicing” (actually, trying to learn) a new karate kata (form). I thought I had memorized all the steps, so I started executing it in solo practice. One of my instructors came running over and told me, “Stop messing up that form!” At first, I had no understanding of what she meant. Some time later, I finally “learned” what she meant – without any verbalization. There was no coherent WHOLE to what I was doing. I was so intent on the verbal description and trying to follow it that I was not actually DOING the form! It was enlightening that she could “SEE that without any discussion at all!

If we are trying to improve at chess primarily relying on sequential verbal descriptions, I suggest that we will NEVER satisfactorily achieve our goal!

13. GEEZ! Correction time again:

"Perhaps the most important of all, to wit: Advance the Pawn which retrains two Pawns. This principle can be more broadly expressed in the following general form: apply a unit of force which restrains anther force of greater strength.”

"Perhaps the most important of all, to wit: Advance the Pawn which restrains two Pawns. This principle can be more broadly expressed in the following general form: apply a unit of force which restrains another force of greater strength.”

I ran the Spelling checker three times across this comment - before posting it!

14. There is an elephant in the room, for sure!

15. lichess.org Puzzle #oFIvA
From game 3+2 • Blitz
avanthikanc (2010)
Yunierpazos (2064)

FEN: 2r3kb/2q4p/1ppr4/p1p1p1P1/P1P1Qp2/3B4/1P4PP/3R1RK1 w - - 2 28

The d6-square [1:1] and h7-square [2:2] are B.A.D. White has the right to move first. The Black Queen has the Function of defending both squares. Ergo, remove the defender from the d6-square by capturing with check on the h7-square. The LoA d1-d8 is opened by the double capture on the h7-square. 2. Qxh7+ Qxh7 29. Bxh7+ Kxh7 30. Rxd6 Black loses the Exchange and his pieces lack scope. White gets a centrally posted Rook on the open d-file plus an outside passed pawn that can be protected and advanced.

16. lichess.org Puzzle #u6UVk
From game 10+0 • Rapid
J0j0 (2013)
kyledavidson39 (2004)

FEN: 5rk1/2q2ppp/8/n4p2/1Q6/6P1/1PP2P1P/rNKRR3 w - - 1 26

This position is one ply before the puzzle position.

Should White attack the Black Queen with 26. Re7?

No. The b3-square is formally B.A.D. [1:1 – WQb4 vs BNa5] because of the absolute pin by the Black Queen on the c2-pawn. Defense of b3 by the f7-pawn is illusory. 26. Re7 creates a second B.A.D. square; both B.A.D. squares are only defended by WQb4. One B.A.D. square can be defended (generally) but two B.A.D. squares ‘protected’ by the same defender is suicidal. Black takes advantage of the overloaded Queen by attacking the White King from the first B.A.D. square, followed up by capturing on the second B.A.D. square. 26. Re7 Nb3+ 27. Qxb3 Qxe7 winning the Exchange.

It is very important to “SEE” B.A.D. things BEFORE making the next move!

17. DANG! Another correction:
"Defense of b3 by the f7-pawn is illusory."