First I have to say I love your guy. Very handsome. For A circuit hunters he has to be through from behind. He has to push into the contact and round. He isn't tracking up in the video which is what they are going to want on the A circuit. Pick up contact,not like a dressage rider, but a long and low contact and push him into the bit from behind. He looks like he has been trained to hold his head in this spot and not really asked to use himself from behind and come into the bit. I don't think he is scared of the Pelham at all he just hasn't been taught how to come through. If you'd like change to a d ring snaffle just to see but I really don't think that's the problem. I'm more for putting the horse in what they go best in. Pelhams seem to be a trend in the hunter ring now for years, if he goes nicely in a d ring go for it.