Fixing HH’s throwing motion at this stage would be a monumental undertaking. I’m really surprised someone didn’t fix that early on. He’s got such good size to throw over the top, but throwing from the side like he does, it’s like having a 5’10” QB back there. Changing it now requires so much thought every time he throws that it becomes mechanical. And just like the golf swing, if you’re thinking about technique, then usually the results falter. I would guess that someone probably tried to adjust him, but when you get under the gun, you revert back to what feels natural.
I have no doubt he would work his tail off, but it’s just a big change.