The most that a crop or spurs can do is act as a reminder. I know, I had the slowest Thoroughbred on record, and I always wore Prince of Wales (blunt) spurs and carried a jumping bat. But they were simply to put her up in the bit and remind her that a big fence was coming, not to beat her or cut her sides bloody (not that you could with blunt spurs - they're about the diameter of your thumb and rounded on the ends). If she hadn't wanted to hunt or run three-day, there is no way she would have. And she kept on wanting to even after arthritis put an end to her career at age 27 -- jumping fallen logs in the pasture and galloping for fun.
And believe me, riding seriously requires that you be in excellent physical condition and have good balance, body awareness, flexibility, and strength. And that's quite apart from the specific skills needed to guide and control a horse.
I could convince you of this in less than thirty minutes on my mare at the end of a longe line.
I am 100% positive you know what you’re talkin about when it comes to horses. I will even admit to being wrong about making a horse do what it doesn’t want, with spurs and whips.
I still don’t believe a horse is an athlete. I reserve athlete status for people. I’m sure you disagree but my standards are my standards.
I do wish you could convince me with your mare though, because I am the only person in Texas over the age of 2 who has never ridden a horse. :-/