In my opinion, it would be hard to determine if he is the dominant one unless other bucks were in the area of view. And even then it would be difficult. There is almost always another bigger buck in the woods at any one time due to travel routes taken on by bucks during the rut. The buck you rattled in, was just intent on finding out who was doing the fighting, so he can determine if he should join in or not. I have ssen this many times when two smaller bucks go at it, and a spike or a forkhorn come running to see what all of the comotion is about. I have also seen in the past 3 weeks, two basket racks going at it hard, and then a nice 10 point shows up, and both basket racks quit fighting each other to take on the 10 pointer. It was over before it got started. The smaller bucks wanted nothing to do with the larger one.