This reminds me of something the famous Indian coach RB Ramesh once said about playing superior endgames: You should think about the drawbacks of the opponent's move!
This is yet another example of ignoring the opponent's threat by creating your own equal or stronger threat! It is also a good reminder to continue to seek aggressive, forcing moves in the endgame.
This strikes me as an excellent example of ignoring the opponent's threat, making the move you really want to play work. It also shows the acute feeling strong players have for the importance of piece activity relative to material.
As soon as I saw the move on the board, it made perfect sense. But my friend (who is also a master) and I hadn't predicted it while quickly playing through the game solitaire chess. I think this is a perfect example of a strong positional forcing move.
In the Petrosian-Botvinnik game I mentioned last time, I really enjoyed some of Petrosian's aggressive moves that a cursory examination of forcing moves (checks, captures, and threats) wouldn't necessarily catch.