Chess.com has a function called "premove". When pre-moves are enabled, while it’s the opponent’s turn you can make a move to automatically be played as soon as they make their move. The premove will play automatically even your opponent does something unexpected. If your opponent's move makes your pre-move illegal (such as putting your king in check), then your pre-move will be canceled).
My question is, under what circumstance should I use the premove function? I can think of the following scenarios:
- My opponent has only one legal move. In this case, if I can determine my reply to this move, I may consider making a premove.
- When I am in a very safe endgame (for example, KR vs KB, where I will not lose even after blunders by my rook) and I am running out of time.
- In the early opening stage of a blitz game, when my opponent has only one reasonable move and for most of his "unreasonable" moves, my premove is still a good reply. For example, after 1. e4 c6, 2. d4, as white I can more or less safely assume black will play 2... d5 and (pre)play 3. Nc3 before black makes his second move. Even if black played 2... g6 or 2... d6 or 2... Na6, 3. Nc3 is still a sound reply.
Why is there such a function "premove" in the first place? What is the "best" way to make the most of this function?