Hook kick.

I think I finally understood how to do a hook kick. It does not solve the problem ;-).
I started to think from Outside Crescent, which I can perform. Well, almost can.
It is almost impossible  to tell, but the vital difference is what you're actually striking with.
A Hook Kick strikes with the heel(at least it must be more powerful) or sole(least powerful, but still...) of the foot. An Outside Crescent strikes with the edge portion(knife edge?) of the foot.
The Crescent uses more of the hip for power while the
Hook uses more of the butt and hamstrings for power since the angle is different.
And here comes the problem with my hamstrings........