A police dog trainer once told me that to take any dog out, if you hit them in the nose hard enough they are done because in attack mode they can only breathe through the nose . he said it is better to offer your left arm then hit the dog as hard as possible straight in the nose to make it bleed and it will have to let go. Same goes in a rescue , I would hit the dog in the nose with a large object to make it let go to smash its head and try to crush it. Another option is the body slam, if it was locked on to me, since I out weigh it, I would try to slam it with overwhelming force against the sharp edge af a wall, tree, post, fire hydrant, car etc to try and crush its ribs and lungs . Another option to rescue another is to grab both hind legs and rip them apart and kick in in the soft stomach
Your advice seems sound, but everyone should also know that pit bulls have an extraordinary ability to withstand pain.