Some very good points Doc, as well as some excellent points/ comments by the other posters.
Before I went into law enforcement, I was a member of a college judo team. Came in very handy out on the streets. Like was said, alot more about grapling, etc. than actual blows. However, effective blows, particularly when out numbered, can be crucial. Hate to tell you what I did and what used. Let's just say if I had an opening I took it. I'm still here. BTW, never hit anyone with your fist unless it's something "soft" like a nose, etc. You'll break your hand on his jaw and then you can't use that hand for weapons like guns.
Like somebody said, he who moves first, usually wins. You really need to see it coming. Above all, your intial, first move must be effective. If it isn't, you are real danger of losing in a very bad way.
Yes, your opponent will try to take any weapons from you and probably will use them on you. When I went through my police training, we were told that 80% of the cops shot dead were killed with their own weapons.
Last of all, never worry about using excessive force. I've seen people die over such concerns. At worse, remember, "I can can explain anything but my own death."
Yes, I, too, have had to fight for my life and my weapons hand to hand. More than a couple of times. I've seen others try this and some of them failed. We buried a few of them. E