BELGIANS, anyone here have used them for jumping competition?

I've seen both Percheron & Shires in jumping competition but have not seen Belgians in action other than photos. Is it do to the breed characteristics & conformation that both the Perch & Shires are the favored draft horses for competition? Sheer miveness of size I would not think relevant. Tho the Belgian is considered a medium sized Draft, I have seen Belgians EVERY bit as big & as strong as Percheron. Heck, my neighbors across the road from me just sold a Belgian gelding to a proprietor up in Sitka Alaska, because at PUSHING seventeen & a half hands they considered him to BIG for driving!!! Myself, as a teenager in the mid sixties, I worked a pair of Belgians to skid both BIG 2nd growth Dougl fir & MIVE old growth Ponderosa pine. We'd section the trunks into 21 foot lengths & hook up the team to them using chokers. They'd strain at first but once moving, pulled that WET HEAVY lumber clear to the landing dock. Strength a plenty for jumping, so why not as popular?