zen, even if the top of the skull is a vulnerable point, I don’t know that I’d recommend such a defense to most people.
I do quite a bit of sparring and consider myself pretty good with my hands and feet, but I have little faith in my ability to land a perfectly placed hammer fist on the top of a charging dog’s skull.
My views are largely influenced by work I’ve done against wrestlers trying to shoot on me, which is probably the experience I’ve had which most closely parallels an onrushing dog. IMO the best option against a shooting wrestler is to sprawl, probably not your preference against a dog. Tho I love kicking, especially with my lead leg, and my long legs give me considerable range, I find the head of a shooting wrestler to be an incredibly tough target. Plus, if the kick doesn’t incapacitate them, you get caught on one foot. Also, trying to kick a dog’s head leaves the possibility that the dog will grab ahold of the leg. I’ve seen too many people cut up their fists on guys’ teeth. Not eager to find out what would happen to my foot/leg against a dog’s canines.
If I’m going to punch, my preference is uppercuts, while at the same time angling your lead leg away from the attacker. I assume, like a wrestler, the dog will likely go for your lead leg - whatever is closest to him. Of course, for a wrestler, uppercuts make his shoot more difficult. With a dog, it might bring his mouth up to areas you’d less like him to attack.
All in all, I see dropping yourself to deliver the type of blow you describe as a relatively low percentage shot, which somewhat restricts your follow-up options (i.e., you have to get down close to the level of the dog’s teeth to deliver the shot). An alternative, which I also train against wrestlers, is to redirect the shooter’s head with a hand pushing down and away, while angling off to the side, and kicking.
Finally, I’m reluctant to choose as my initial option a course of action that has such a high probability of injuring myself (broken hand).
In suggesting kicks to the chest, I tried to figure what most average people not trained in fighting could pull off. Me, as I stated, I love to kick and work at it a lot. Moreover, I have had big dogs for the past 20 years, and am very comfortable with them. And tho I love dogs SO MUCH, and am very confident in my ability to intimidate even large aggressive dogs when necessary, I would have no compunction against kicking a dog to death or swinging it repeatedly into an obstruction if it attacked me or my loved ones. Cheery topic, hey?
I guess no one has stated the obvious, yet, that dogs can’t climb trees or fences.
Now what do we do if someone comes after you with a pointed stick?