A Waterford mouthpiece makes it very difficult for the horse to lean on and the full cheeks help with steering. The running gag raises the bit in the horse's mouth while applying pressure to the poll. Overall this bit is advantageous to the rider helping with control of strong horses.
"I ordered this bit a couple of weeks ago and find that it works really well with my extremely fit hunters, I have used this on a couple of my horses already with a positive outcome." Sally Hayward