Blunder check

A blunder check is a brief pause between choosing a move and playing it. Its purpose is not to search for the best option again, but to catch an immediate consequence that was overlooked, such as leaving a piece free, allowing mate, or exposing one's own king.

1. Imagine the full move: remove the piece from its starting square and place it on its destination.
2. View the resulting position from the opponent's side and inspect checks, captures, and threats.
3. Check whether a piece became undefended, a row, column, or diagonal opened toward the king, or the moved piece can be trapped.
4. If a dangerous reply appears, return to calculation; otherwise, play the move.

This routine catches mainly one-move oversights and failures of board vision, such as attacks or defenders that were present but unseen. It does not guarantee that the plan is good or uncover every long-term consequence. With little time it must become shorter, but it should retain at least one question: “Which reply restricts my options most, such as a check or capture?”.