I'm definitely not a jumper, but I was under the impression they were so that if you horse hits a bar, it can feel the bar hit its legs and helps to make sure it doesn't continue to knock down bars and possibly injure both itself and its rider.
Really, boots end up being personal preference on what you end up using.
Poseidon is correct....open front boots were designed to let a horse know if they have touched a pole or not. Most horses don't want to touch them, so if they accidentally rub them once, they are more likely to be a bit more careful the next time. Posted via Mobile Device
I've ridden green horses that can't stand touching a rail and old campaigners who can get complacent about knocking things down. Depending on the horse I think it it can benefit a lot of horses to feel it when they hit something. It's hard to say if it's going to help your horse out, you need to first figure out if your horse is just being lazy or if he needs some conditioning/training to increase fitness and jumping ability. IMO jumping horses in boots is an all around good idea regardless.
OPen front boots also protect the tendons from being hit by the back feet etc.
I love my open fronts they are leather and secured with cross straps with lambs wool interior they are my show boots obv I have other cheaper ones for playing in
All horses I think should wear boots jumping for protection my guys all wear open fronted tendon boots over reach boots and then some wear back brushing boots to