1) He's leaning forward, proving you wrong, since his punch is obviously powerful enough knock down his adversary
2) His lead leg is stopping him from falling off balance on his right hook, the lead leg is stabilizing him, the power of the punch comes from his rotating upper body/arm
Which contradicts quite a bit your previous statements
I'm just stating the facts here
You're blind. Opposite leg provides power for the punch. I'd demonstrate physically, but you can try it on a heavy bag yourself.
Try throwing a right cross powered by your right foot, it doesn't work, it's weak.
The opposite leg is providing support for the weight transfer of the whole body in the case of a hook or a overhand
Don't lean forward my ass
https://i1353.photobucket.com/albums/q669/mightyfighter/maidana-overhand_zpsed5b329b.gif
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