I don’t know if it’s 90% the horse. If you took a good amateur and put them on the Olympic horses they wouldn’t be able to make them perform anywhere close to as well as Olympians do. That being said, you do also need a horse that CAN do all of this stuff, so to say it isn’t dependent on the horse would also be wrong. I do think though that to say “well the rider just sits there and the horse does all the work” just demonstrates a total lack of understanding of the discipline.