Pressing the clock does complete the move but the game immediately ends when checkmate, stalemate or a dead position is reached (checkmate not possible by any legal series of moves).
It is always best to hit the clock to remove any doubt though.
But not if the move played happens to be illegal, in which case, pressing the clock completes the 'error'.
True. The move creating the position has to be legal
But I feel that in the original post, even if White plays an illegal move, Black cannot be declared won, since the fact that Black cannot escape the otherwise forced legal mating sequence remains unchanged. This is similar in principle to the running out of time scenario.
Pressing the clock does complete the move but the game immediately ends when checkmate, stalemate or a dead position is reached (checkmate not possible by any legal series of moves).
It is always best to hit the clock to remove any doubt though.
But not if the move played happens to be illegal, in which case, pressing the clock completes the 'error'.
True. The move creating the position has to be legal