The hands, though possessing some intrinsic power ( for instance whipping and dead hand), really are best when used as ways to connect your body to that of the opponent.
You move your feet so you are aligned with your power and potential future options, and go where your opponent is weak and has none. (a.k.a. being pretzeled). Connect your body to your hands and voila! You can use your legs and the planet earth to add force into the system.
What is going to work when, will vary depending on the opponent. It matters not! There's always somewhere that will! See the momentum and connect. The reaction to the entry will tell you if you succeed, or how to counter their resistance.
Edit: I have been told that the link above has been changed to 'private' which is unfortunate, but this one was just uploaded: https://www.youtube.com/watch?v=5RhzXsP8LEU
It has some of the same entries and progessions as the previous clip - Basically using one idea and extrapolating.