Actually, yes, the dog you're pinning can break free and get you. Or your dog could come in and have a go at the dog you're pinning, and hey, you're in the way and now you really have problems. Two dogs in fight mode will not care if their owner is in the way. It's probably been posted in this thread already, but if you haven't read it, check out Leerburg's article on how to break up a dog fight
. They sum it up pretty well.
"Dog fights are a very dangerous thing to try and break up alone. You should never rush in and try and grab the dogs to pull them apart. They are in high "fight drive" and are not thinking clearly when fighting. If someone grabs them they will bite without even thinking about who or what they are biting. This is how your loving pet can dog bite the living crap out of you in about a second and a half.
In reality it probably doesn't even know it's biting you. I compare it to a bar fight. If a person comes up behind 2 guys fighting and just reaches out and grabs the shoulder of one of the combatants most of the time the fighter is going to turn and throw a punch without even looking at who or what he is hitting. This is because his adrenaline in pumping and he is in "fight drive"."
Dogs are fast. They'll react to a touch in a dog fight with a bite, and will nail you before you have a chance to wrestle any dog to the ground. It took three people to hold my Doberman so we could take stitches out, and that was in a highly controlled setting at the vets, with people he knew and trusted. He wasn't in fight mode and his adrenaline wasn't up.
Griffin is the same dog that I have muzzled if there's a test that requires him to be placed on his side or back. That's because he's so darn fast, if the vet went to pin him, he'd bite the crap out of her because he does not want to be pinned. I know that, and I'm up front about it. My vet completely understands too, that's not unusual for a lot of dogs to not tolerate being pinned by someone they don't know.
Your best bet if your dog is being attacked is to have a second person there and to break up the fight properly. The hardest part is keeping yourself calm, especially when your dog is the one being attacked. I've had to break up a fight solo, and that sucked. I accomplished it by cutting Griffin loose, because I knew he'd run home as soon as I got the other dog off of him. The second dog, I got by the back legs and swung her off. She wasn't clamped on, which was fortunate. And once Griffin took off, she quit fighting me.
I was seriously lucky though. If Griffin had decided to fight, it would've been a lot worse. I don't care to think about what would have happened if it had been my first Dobe Logan instead of Griffin. He wanted to kill other dogs, and let me tell you, he'd blow me off in a second if he saw another dog.
I know your mind is probably made up about pinning an attacking dog, and nothing we write is going to change it. But seriously, at least consider it. There's a lot of experience on this forum and a lot of folks, myself included, have experience in dealing with dogs who are dog aggressive and reactive. We know what we're talking about and we'd rather not see someone get put in the hospital because they thought they were faster or stronger than a dog in full fight mode.