I've been thinking about this aspect the entire time and actually feel very guilty about it. I had physical control of my dog the entire time. It limited my options and it severely limited her ability to defend herself. My reason for not letting go was that at least with her close to me, we had control of one aspect of the encounter and just had to stop the aggressor. If I let her go, she is very fast and there was no telling where the encounter would spread to, but it would/could move elsewhere much faster than any of us could run. I'm not sure that was sound logic, but at the time letting go seemed like a risk. I actually told my wife after that I should have handed off the leash to her at the first sign of trouble. Let her deal with maintaining control of our dog while I fully engage the threat. Again, not sure it would have been correct. Had it been multiple attackers, at that point I would have let her go and hope she could hold her own against at least one of the attackers, which she probably could.