There are 2 general aspects.
1 learning and practicing aspect.
We have to break down moves into sequences of parts. For example, in qin na or shuai jiao, even thou we have to execute everything in an instant, but for practicing purpose, we may initially break them down into step 1. 2. 3 etc.
Once we are familiar with each part, then we practice to do everthing as fast as we can.
2. tactics and strategy
Most of time, we may win and defeat the opponents by being faster.
However, if the opponent is somehow faster than us, we have to do some slower moves to take back the initiative.
Be slower in starting or initiating or move away away his first or first few moves and gain advantage somehow to start our counter move or move earlier than his next move.
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In Tai Chi, however, we like the precept of following the opponent. In that case, if the opponent is fast, we are fast. If he is slow, we are slow.
which is very difficult to do, and beat the opponent at his own move.
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Just to add some thoughts.