The risk of the TCMA hammer fist

[YouKnowWho]

http://www.youtube.com/watch?v=vY1Hi...eature=related

At 1.38, when you use right "hammer fist" on your opponent's left arm, your opponent can borrow your force and sping his left arm into a hook punch at your head.

http://www.youtube.com/watch?v=pOD_MuvzcwY&NR=1

IMO, this will never work in combat speed. The reason is the hammer fist has to travel much longer path than a jab. If your hammer fist can hit on your opponent's arm when he applies a straight punch, you must be much faster than him. If you are much faster than your opponent then anything will work.

There is a good reason that "hammer fist" is not commonly used in the western boxing. It's just too slow to be combat realistic. What's your opinion on the "hammer fist"?