Help me understand the action of the bit in the OP’s first post please. I look at it and see a double jointed D ring snaffle with a big centre section. With the D sides, I can’t see how the centre piece wouldn’t lie flat on the tongue, and the two joints provide the same sort of action as any other double jointed snaffle (i.e. draping over the tongue versus a nutcracker action of a single joint.). It is wider than the middle part of a conventional double jointed snaffle though; does that change the action dramatically? What I would think is that if anything, the big middle section would prevent a horse from putting their tongue over the bit. Yes, there are the points on the inside, but I’m not sure I can see how they wold come in contact with anything really, lying on the tongue?
If this bit had full cheek sides and was held in a certain position by the keepers, I can see it having a dramatically different action for sure, but I guess I’m missing something given the D-ring cheeks?
I’m not saying it is or is not right for the OP’s horse, just trying to understand the bit’s reputation as a train stopper. I can’t remember if I have one in my collection or not - if I do, I’m going to have to dig it out to play with!