What is speed in fighting? Is it the velocity of your hands, feet and body movement? Or are there other, prevalent essentials in a good fighter? What is a good fighter?
A good fighter is one who can hit his opponent quicker, harder, without much perceptible effort, and yet avoid being hit. He doesn't only possess a pair of fast hands and feet and quick body movement, but he has other qualities such as non-telegraphic moves, good coordination, perfect balance and keen awareness. Although some people are endowed with a few of these qualities, most of these attributes are developed through hard training.
All the strength or power you have developed from your training is wasted if you are slow and can't make contact. Power and speed go hand-in-hand. A fighter needs both to be successful.
One immediate way to increase your speed at impact is to "snap" or "whip" your hand just before contact. It is the same principle as the overhand throw. For example, if you throw a baseball with a full swing and snap your wrist at the last moment or the tail end of your swing, the ball will have more velocity than without the snap. Naturally, the longer swing with a snap will have more acceleration at the end than a shorter swing with a snap.
Speed in Punching
The backfist is not the quickest or strongest technique because you can't utilize your entire body in the movement. It is, however, one blow that you can apply the whipping or snapping motion to.
The backfist is usually thrown at your opponent's head, and it is used heavily in combination with lop sao (grabbing -the-hand techniques). It is delivered from shoulder height but can also be used as a surprise attack and can be launched anywhere from your waist to your shoulder. It is very difficult to block once you have acquired non-telegraphic moves.
Although some power is lost in this punch, it is compensated for or redeemed when combined with lop sao.