They may feel about Bull Mastiffs doing protection or bite "work" the same way I feel about Filas being involved in it; that a well bred, well socialized (and that gets me in all sorts of hot water with a lot of the Fila world, lol, but the proof is in my dogs) one has all the natural instincts to protect properly and that bite and protection work is, in fact, a game, and that we do not want to send our dogs the message that this is ever a game.
Also, there's the spectre of the public seeing our dogs "attacking" for sport. We have enough problems with a segment of the general public thinking they are man eating monsters as it is
That being said, I'm not ready to condemn anyone who wants to engage their dogs in the sport, as long as they don't start touting how "badass" their dog is. The Mastiff breeds don't need that. All we have to do is look what it's done for the Bully breeds. But I don't think anyone who would put time into a forum like this would be someone who has that mindset
