It seems too many people have too much time on there hands to come up with something like that......Not my thing, because a good frame comes from a horse moving from behind and lifting his back and everthing falls together from there usually.
Just another gadget. Its a great idea for whoever designed it, tons of people just eat those trick and gadget things up, the thing will probably sell good. But as a buyer/horse owner ya gotta watch out and not be fooled
I agree that you shouldn't need a piece of equipment like this to tell if your horse is on the bit. But, it won't "ruin a horse's true self carriage". This is not like a chambon, neck stretcher, draw reins, etc. This just assists the rider by showing when the horse is on the bit, it does not create a false frame, the rider still has to put the horse on the bit.