|White to move|
After "thinking" for 21 minutes, I decided to have a look at the answer. Although I tried to zoom out mentally, I didn't see the main idea behind the combination.
What is needed to find an idea on level 3? The checklists that reveal intricacies about level 1 and 2 are no longer conscious in use by me, since they don't address the main flaw in my approach, and it is a lot of work for something that doesn't work most of the time. I use a checklist for level 4, the orientation phase, and that works well.
What I need is a checklist for level 3, as a kind of training wheels. Had I for instance asked in this position "how can the white knight and the white queen collaborate together?", then I had seen the main idea behind the combination immediately. Once the idea is found, the accompanying moves are usually found fast. That is not the problem. I'm going to try to develop a level 3 checklist. I'll be back!
For your convenience:
Level 1 = chasing letters = t&e = chasing individual moves
Level 2 = chasing words = recognizing motifs
Level 3 = sentence = combination
Level 4 = text = solution
(maybe someone can formulate it a little bit less informal)