How does an amateur play the opening? Level: Amateur

Usually, by following general opening principles.

He keeps in mind concepts such as the rapid development of the pieces and the economy of tempos, the control, and occupation of the center of the board, securing the king's safety (typically with 0-0 or 0-0-0), not wasting tempos by playing a piece several times, not to waste tempos with useless pawn moves, not to weaken the pawn structure itself with doubled pawns, isolated pawns, or squares between pawns that cannot be quickly or economically controlled. Some, more advanced, have heard about the harmonious arrangement of the pieces or that a game plan needs to be developed as soon as possible, perhaps after having moved most of the pieces of their initial squares.

Is there a flaw in playing the opening like this?

Sometimes.

In a broad sense, playing chess is about seizing opportunities and creating conditions for favorable opportunities to arise. In this context, the general rules serve as a quick guide to sensibly place the pieces and pawns for later actions, but not as a replacement for observation and concrete analysis of the situation.

Observe and analyze what?

Activity. The action of the pieces is influential in the opponent's logical choices.

The amateur is told repeatedly not to initiate active actions before he has completed his development. In much because it is risky, complicated to handle with precision, and most of the time unjustified if not refutable.

But it is possible and even justifiable. If the conditions exist, a single piece can achieve serious defensive concessions; two coordinated pieces can give checkmate, and so on. An incomplete development or the possibility of incorporating reinforcements should not be underestimated. The point is that the existence or lack of "conditions" can only be established through observation and concrete analysis of the activity. The activity found is the guide to knowing what and how to play. The general opening principles, in such situations, are relegated because they are guidelines for the prelude to the active game and not guides during the active game.

Do experts and masters use general opening principles?

Yes, but usually subordinated to the concrete in the opportunities and problems that arise on the board.

Let's start with situations where "memory" is not the source of the moves. For example, suppose the opening is being played as a prelude to active play. In that case, it is common to be guided by the pawn structures (and the possibilities of modifying them) to establish which plans can succeed later and develop the pieces accordingly, at least until the activity on the board requires concrete answers and solutions.

Suppose by own or the opponent's decision, the opening has taken an active and dynamic character. In that case, it is –immediately– tried to establish the axis of activity and their supporting logic as criteria to develop the game. Then, as in the middlegame and the ending, you think specifically about the problems and their solutions.

Do you mean that it is incorrect to follow the general opening principles?

Not at all. Sometimes it is possible to limit the rival activity during the opening to bring the crises to the middlegame or even the ending. The point is to recognize that the present or possible activity determines when the general principles are totally or partially valid or should be set aside. And this is important because risks can be taken to accelerate the crises (even in the understanding that they are not "correct" and that it will be challenging to conduct the game with precision), just not to let the opponent have an "easy" game.