hard to know what you are saying...lets try it this way, as a reference point (I'm not advocating these illustrations are correct for maximum power, in fact, I know they are not )

bag2.wmv - simple no step reverse punch...about 3/4 power.
1st punch with leg locked on impact and heel down.
2nd punch with rear leg bent slightly and heel up a bit.

bag1.wmv - one step elbow and one step natural stance (shizentai-dachi)
elbow - I overrotated/exaggurated the hips, but you can see how the hips lead the strike.
step punch - tried to whip or wave or whatever it's called in 2 directions. by the vertical plane (notice again the hip-lead creating a forward arc) then in the horizontal plane with the hips/gamaku.

strikes were with a 3/4 twist fist, if that matters to anyone. I added slo-mo for your convienence...wasn't that jolly nice of me?

this is different power generation than what I'm used to...remember, I'm trying to figure out the dynamics for Shorin Ryu or MB if there is a difference. and I am actually thinking about this in terms of style...since it has to kind of fit the fighting philosophy of what I'm studying....or does it? anyway, thats what I'm finding out.