That's the question

The question.
In my previous post I formulated my question. Without a question you can't get an answer. So defining the question is all-important. Today I started to look for answers in Kotov's "Think like a grandmaster", a book that I only had glanced thru once. I did some testpositions and the results were pretty revealing. Especially if I take the position into account too on which I worked for 7 seven days lately.

The misconception.
I used to think that the difference in calculation skills between amateurs and grandmasters wasn't that great. That the real difference was made by the amount of patterns each could recognize. In fact that was what prof. Adriaan de Groot stated somewhere in his scientific work. But now I found out that that is not true.

If the problems of Polgars book and Kotov's book are the standard, then grandmasters can calculate much better than me. What is more, my latest experiments with deep calculation convinced me from the fact that I can do much better than I do right now. The idea that I have reached my upper limit of calculation skills is utterly nonsense. I have just deceived myself with that idea.

Lately I read a scientific research which refuted the statements of prof. de Groot.
Prof. de Groot based his conclusion that amateurs and grandmasters don't differ much in calculation on research with rather simple problems. But the refuting study was based on much more complex problems and a big difference in calculation skills was shown. So the accent of my work shifts from pattern recognition to developing more calculation skill.