My old iron palm trainer had very flat knuckles due to the build up of bone from hitting hard ****. He said the goal of the iron palm training was to eventually be able to punch so that all knuckles hit at once. I can only imagine the arthritis he is going to experience in later life, his hands were so gnarled it was almost grotesque.
Damn. Got all excited when I saw this thread...I was hoping for something like this:
YouTube- Wall Kick
stretch your arm, make a fist, now look down your arm like you would down a poolque or rifle to see if its straight.
notice how the two outward little knuckles are out of allignment of your arm.
it makes much better sense, connection wise to hit with the two big knuckles as they are in the same line as your wrist and arm.
That kicking video was epic. Make a new vid OP but this time throw a hard overhand. That would impress me. On a sidenote I cut my knuckles pretty bad punching a tree once.