The amount of force that can be applied to a hook hand technique is relatively minimal. Most importantly, however, is the fact that the wrist could be easily injured while striking with the hook hand. I've attached one as a link, but provided addresses for two separate essays. The amount of force that can be applied to a hook hand technique is relatively minimal. Conditioning No amount of conditioning would prevent you from injuring yourself using a weak technique.
Double wind blows against the ears, hit tiger left and right.
Push is not double yin, except at a beginners level, the two hands interchange yin and yang as they move. Ditto for press, cross hands, etc. Fighting is the same as barehand - from form to individual application to two person sets to free fighting. Read some of Vincent Chu's articles. Guess you haven't seen those.