Friend has a youngster that she wants to show but think she should be in a double, seems cruel to me so wondered what age you could introduce a double?
Sorry didn't mean to imply they are always cruel and in the right hands yes they are very good tools, i meant more in the way that are they really necessary for youngsters? And if so what is a good age to start using them?
Depends on the class your friend is doing. Unless it is something like a novice ridden class that stipulates a snaffle it should be in a double. However many competitors use Rugby Pelhams these days particularly with ponies.