Chimera Kennels

Your video link didn't work for me.

The dog did what it was supposed to do. Since you asked (by email) for me to comment here, I will say at 6:30-6:40 or there abouts the dog's pitch got pretty high. Without being there and knowing more about the dog it would be difficult to say if the dog was over stressed or if the dog was switching to prey, but I would tend to say the dog was showing signs of stress even though the tail is still up and the dog is forward. If you notice around 7:00 after the win the dog's pitch is back down and deeper and seems to display more confident (since he just won) as the guy puts distance between him and the dog again. For this reason, I would work on proper bite and grip and reward COUNTERS. This will help the dog progress.

Again though, overall...the dog did what it should and proved willingness to engage a home threat while also displaying stability. Good job.

A counter is when the dog does something that illustrates a greater willingness to engage or fight the decoy. Rewarding counters should be done progressively. Work at the level the dog is capable of, and then when it shows SOMETHING that illustrates he is willing to engage more, reward him for it.

A counter could be more pressure on the bite, a fuller grip/deeper bite, a shake, forward motion in attempt to climb on the decoy, etc.

Nice video, looks like he is very willing to engage the threat and is a pretty imposing looking dog as well.  By the way, I noticed at the beginning of this discussion that you mentioned that the individual that gave him to you said he was a bullmastiff, but just from an "outside perspective" he looks a good bit like a tosa inu as well (not that it matters).  Anyways, looks good.