I have a pack of six, one is a JRT, five are German Shepherds, and four of them are intact females. I allow them to correct each other fairly, but put a stop when it goes over the top. Even with four intact bitches, I have never had a "bitch fight" because I monitor all interaction and know where each dog stands. My alpha bitch, Kyniska age 3, and my newest bitch, Indah age 1 1/2, have never fought even though there has been tension. Indah likes to jump my 7month old because she is smaller and, as such weaker, and I put a stop to it when Kyniska doesn't. If Kyniska gets involved, Indah is fairly put in her place. Indah doesn't back talk Kyniska, and if she did, she would be corrected because she isn't alpha.
The only time, recently, when Kyniska went over board, was after Indah did the "shake off" and was back into a thinking state (instead of reactive state) and Kyniska should have backed off, but didn't. I verbally corrected Kyniska, and told her to leave it. Kyniska is pregnant and hormones are playing a role, so she was feeling more need to make her point. Indah got the point without Kyniska needing to over do it, so I stopped Kyniska.
When three of the last litter were visiting, two sisters, one brother, the sisters got into it. Owner of one was very upset and didn't know why they were "fighting." I explained that female A was upset and stressed because brother wouldn't stop humping her and she finally had to tell him off. When puppy B approached and did a normal behavior, female A overreacted causing a disagreement because puppy B didn't appreciate the overreaction. Being sisters there is already sibling issues, so they're more likely to get into it anyway.
My point, having a pack, or even just two dogs, means you need to know what's going on around you with them. NOT just with their pack order. One dog being stressed physically, or mentally, can cause issues. Factor in unstable or dogs with issues, and you REALLY need to know.
It also helps to have knowledge and understanding in their communication as well. What the difference a tail wag means when its stiff vrs flowing. The height its at when its wagging (and even the dog and how their tail normally sits via height). Licks of the tongue, where their eyes are focused, ear set, even add in where their heads are turned all can explain why a dog fight started. It's this knowledge that can prevent a fight, before it starts, or to figure out who to correct if it has started before you can prevent it.