I went the WEG last week. A few times I took a break from walking around and sat near the schooling/warmup rings to watch the riders prepare for their upcoming competitions. I'm not sure if I was watching jumpers or eventers, but in all cases, the horses had martingales on that were so tight, the horse's couldn't even get their heads to the vertical, no less in front of it or be able to stretch out. In one case, I watched one rider jump her horse over what looked to be at least a 4' vertical several times with the head tied down. Each time the horse bucked after the fence in protest. She finally took it off, and the horse proceeded to throw his head around. I heard a woman next to me remark, "that's why he's in a martingale", but it just makes no sense to me. These are the best of the best in the jumping world. What is the logic to this? I'd post pics, but since they're not my horses, so I doubt that's appropriate.