I see the exact same thing, MM. One gal, also in 4-H, very consistently places first or second in every speed event that a given show offers. Her horse is lightning fast, loves to run, and knows the patterns. She doesn't use a whip, quirt, or over/under. Almost every year she buys a bigger bit, and her dad must stand at the in-gate and yell at the horse to stop as he runs home to keep him from crashing it. He's dented several gates in local show rings, and they've received warnings from rodeos to deal with the problem or not come back next year.
Once the horse is moving, his brakes are gone. I do believe that her current bit is like a cross between a wonder bit and a mechanical hack with a twisted mouth, ridden two handed. Not sure where you go up to from there... Horse's mouth is perpetually wide open, and would be sky high if not for the tie-down.
I don't game much, at least not competitively. I'm no daredevil and have no desire to become one. My sister does about every discipline out there except for "D" Dressage and saddle seat, and generally places well when she does run poles or barrels purely because of the pleasure miles that her horse has under him. Even though his actual times are a bit slower, they ribbon because they left the course intact.
So many people think gaming is all about speed; true, trained brakes and steering take a surprisingly distant backburner for a sport that is all about precision and control.