Yea, I think the trailer size and weight can easily over power any small jig, rendering the shape of the head a moot point. But if you tie a small amount of hair and a tiny trailer, the shape still matters.
To add to what Dave said, I've heard people say a bass will really pop a football jig harder because you can gently pull up the slack in the line and the bait will pivot up because of the shape, making the trailer raise its claws in a defensive position.