Time or Force?
This game has as its main theme a rather continuous struggle between time and force. Time means what is happening right now: it refers to the immediate threats that have to be met one way or another immediately. Force refers to the amount and type of pieces and pawns the players have to deal with.
Each player sacrificed some material in order to gain the initiative. The key questions to ask when confronted with such possibilities are “How much material am I giving up?” (which is best answered by a detailed calculation of the forcing moves, to make sure you don't lose more than you intend), and “How long will my initiative last?”
The initiative is an ongoing situation during a game. One of the players keeps making threats, thus forcing the game into channels of his choosing. When you have the initiative, you decide where and when the play takes place. This is a powerful weapon when used with authority.
The latter question is often hard to answer exactly, but if you have more pieces in play after the combination, and they can continue to make threats, while your opponent has difficulty getting his pieces into play, you can often justify a fairly substantial investment of material.
Get out a set and board, or even two sets and boards if you have them. It is possible to follow a game like this through in your head, but you will miss a lot if you are not very experienced. (White: Master; Black: Expert; Los Angeles, 1981.)