I've been shown a torquing motion with the straight blocks that deflects a bit. I don't recall being shown movement with the cover block for hooks, but I do tend to make a small movement that deflects a little bit. Not to the extent Hannibal does in that video.
Obviously listen to your coach, but my humble suggestion would be to experiment with getting more rotation in your blocks in shadow boxing and see if that makes any difference for you when you go back to partnered work.
In my opinion, with your head up, you are going to recieve trauma to the initial point of impact then trauma from your head rebounding of the concrete repeatedly. You are far more likely to get knocked out this way, which means you cant fight on. It also leaves you in a worse position structurally to escape and therefore prevent further head trauma.
There are so many variables, and a certain amount of six-of-one-half-a-dozen-of-the-other, that definitive advice is not possible. It sounds like you have a specific scenario in mind; namely being punched while mounted. I don't entirely disagree with your advice in that situation, because fists are not so likely to smash your skull into pieces. But don't forget that keeping your head on the ground does not stop the ground from damaging your head! It will always provide an equal and opposite reaction to the force hitting down on your head. If you want to smash something, you put it against a hard surface, because that way every ounce of energy you put into your strike goes into the target. Matts and canvas will change that dynamic somewhat.
I am thinking of mount, you are right, but purely because it was (I think) the fatal position in Tom's initial post. Granted, head on pavement is still going to be injurious; I just think it's the lesser of two evils assuming intelligent, active defence in each case.
The other side of the argument is that any amount of air between you and the ground will allow your neck muscles to take some of the energy out of the strike. With punches, the rebound would suck, but if they decide to drop a forearm on your head with their bodyweight behind it, your neck muscles and a bit of rotation could mean the difference between a hairline fracture and a hole in your skull. I dunno man, it sucks either way!
I am as guilty as anyone. When I watch fights I want to see blood. I want to see head shots. Don't think I can change that but I am more aware of the long term consequences the fighters face now.
