I've posted before on the importance of CCT (checks, captures and threats) in generating candidate moves, especially the importance of not eliminating any of them prematurely. It's often easy to mentally eliminate or ignore possibilities simply because they don't work at the 2-ply (one move) level of thinking. Of course it doesn't make sense in your thinking process to endlessly recalculate capturing protected pieces that would simply result in losing material. But it is worth looking at tactics that might eventually work if the board situation changes, either through what you do or your opponent does.
IM Silman over at Chess.com just published the article "Deadly Mindsets: He Can't/I Can't" that offers a look at this phenomenon, including a very timely example from this year's World Cup (Adams - Laznicka). In the case of this game, it really is a one-move threat, but it visually doesn't look at first as if it should work. These types of moves are much harder to visualize as well, since the tactic involved (a pin) may not register as easily on the mental chessboard, which is what I'm sure Black was relying on at the beginning of the sequence.
In other news, I'll be on vacation for a couple of weeks from both work and chess. Should be good to clear the mind and then return ready to work / play harder once more.