Spot. Sort. Focus. Decide.
When, as a boy, I learnt to plane a piece of wood, I learnt that there is a limited set of conditions that make a good plane stroke. First the blade must grip the wood, but not too much. Then the stroke must go in the right direction, taking into account the direction of the wood fibers. Then the stroke must make sure that the shaving does not block the plane. All this must be controlled by subtle variations of speed and pressure, it is very complicated in the beginning but very simple after you have learnt it.
I have come to the conclusion that playing good chess makes use of the same principle. A limited set of steps that must be taken from looking at the board until making the move. It is up to every player to find his own set. For me, there are four basic steps that repeat all the time: 1. Spot 2. Sort 3. Focus 4. Decide
Just as one plane stroke is not enough to work a piece of wood, one Spot-Sort-Focus-Decide circle is (in most cases) not enough to find the right move and to make it. It may take two, three, four or even more circles.
First step: Spot
Make sure that you have seen everything (targets, attackers, defenders, patterns) before you take the next step. Sources of failure: tunnel vision, not looking at the whole board, missing hidden targets on crowded boards, missing patterns not adequately stored in memory for quick retrieval.
Second step: Sort
As soon as more than one element has been spotted, they must be sorted: Which elements match? Which is the most important one? Sources of failure: Underestimating and overestimating attacks or defenses, miscalculating values of pieces, missing tempo-gaining (intermediate) moves, and the like.
Third step: Focus
Focus on the top listed element. Assess candidate moves: checks, captures, threats, other. Sources of failure: Wrong ranking of candidate moves, for instance, looking at a threat before a check or at a distant check before a close check or at a bishop check before a queen check.
Fourth step: Decide
Is an element not important, discard it to save time. Is the top candidate the best move, then play it. Is it (probably) not the best move, do another circle, taking into account more spotted elements. This is the most important and the most difficult step. It is the step where failures in thinking become failures in moving. It is the step where you may lose too much time for the right decision. It is the step where you blunder by moving too fast.
My next project will be an analysis of my failures at CTS, sorted by Spot-Sort-Focus-Decide. Every problem where I lose rating points, even -0.01, will be eligible for this analysis. Of course failures will occur in every step, but I'll count only the main failure step in problems solved too slowly. In problems failed to solve there are two steps involved, one of them is the wrong decision.