Branch's form is better then it may seem. He is keeping continuous tension on the muscle, and the explosive positive is preceded by a decent negative. His range of motion is also decent.
Not the best form, but again...better then it looks.
nothing to do with it. the argument here is that he's calling them skull crushers and he isnt doing skull crushers- at all.
whether he is keeping tension on the muscle etc is irrelevant.. he might as well be doing bicep curls by your argument..keeping tension, explosive positive and decent negative....
tension, positive and negative arent even form aspects.
form is about positioning the levers and pivots and the weight in the right plane at the right time.