This video addresses the role of the hand on the hip within kata. Historically, tactically and biomechanically, the role should be very clear, but sadly dogma persists around the issue. Bottomline, we should never have an EMPTY hand on the hip and such a motion will do NOTHING to increase power.
The video covers:
1) Why the role of hiki-te is misunderstood.
2) What hiki-te is really for.
3) Why the “power generation” argument is false.