I have seen a fair number of Grand Prix jumpers in snaffles.
Yes, the tendency is to load those horses up with an entire hardward store on their heads and there are very few rules about tack in the jumper ring. The philosophy there is "Better to have it and not need it than need it and not have it."
Most of those horses school on the flat and over low fences in snaffles at home, and get the full hardware store in competition, because the rollback to the triple in the jump off is a bad time to find out you have insufficient brakes or steering. Imagine a horse that you COULDN'T hack in a snaffle; what the heck would you ride them in for a big class?
In re: dressage horses; upper level horses wear double bridles, which actually has two separate bits in the horse's mouth - a small, thin snaffle, called a bridoon, and a curb. Now look at some more dressage photos, and you'll notice that most riders ride off the snaffle rein 90% or the time, with contact on the snaffle rein, and slack in the curb rein. The curb rein is used mostly to influence collection, NOT for steering or brakes. Again, if you needed a curb to steer or stop, do you think you'd have a horse that was soft and obedient enough to ride an entire Grand Prix test?
Last edited by maura; 09-07-2012 at 07:09 AM.