Hibernaculum

Different technique is all.
A boxers hook is with your thumbs vertical upon impact, as you said but they also keep the rest of the arm straight in line with the fist. I think this has a greater ko potential since you're able to throw more weight into the other guys face forcing the movement that hopfully rattles his brain.

A MT hook is with your palms parallel to the floor as well as striking with a bit of a downward motion to keep the elbow above the fist, unlike the boxers hook this punch can be turned into an elbow quite easily if needed or desired.