They're less likely to take it and run with it, I've found, because it doesn't hurt and scare them the way pain from taut reins on a bit can. Obviously it's not 100%, and of course you need to have a horse soft and respectful in a halter on the ground first, but my anecdotal "research" has shown horses to be far more sensitive to see and leg cues and more willing to listen to me, as opposed to running blindly, in the bitless option.
If he has a hot blood breed in him such as Arab, the check and release should work. Otherwise, take him out and lope him for several miles. When they are only loped for short distances, they have a tendency to get excited and use a burst of energy. When they are rode for a longer lope they'll learn to conserve their energy. Kind of like the difference between a marathon runner and a sprinter. They have to be taught this though and taking him for longer loping sessions will do that.
How big is his turnout? If he can't really get up and move there, he will want to move faster when you lope so he can stretch out. Posted via Mobile Device