Riding by Theory or.....
I have had hundreds of lessons in my liftetime with dozens of excellent teachers from all nationalities. Living in New Jersey, not too far from the USET headquarters has its benefits. I have managed to clinic with many International level riders, coaches and judges.
Some have been great, some have been OK, and some have been not good at all. But, I was blessed to have a good, solid foundation in the basics from an exceptional trainer who once told me, "You know enough to separate the wheat from the chaff, so when you ride with someone, do just that." Some suggestions work and some don't, so I've kept the ones that did, and discarded the rest.
My favorite trainer of all time was Lockie Richards, a former three day rider who coached the New Zealand team in three day and eventually turned to dressage. As Lockie used to say, "I got smart and decided I didn't want to get hurt." Lockie had tons of good teachers in his past, and plenty of riding experience, but he never had the big money sponsors to get a superstar horse, so he also had a lot of difficult horses to ride and train in hopes of making it to the Olympic level. (Breggo, the horse of "Lord of the Rings" was his last Grand Prix mount.)
But, all of that experience made him one of the most gifted horsemen and teachers I have ever known. I used to say you could take a fat Shetland pony to a Lockie lesson and when you were done, you'd be riding a fat little dressage star. Well, maybe not in one lesson, but both you and the pony would have learned more than you'd ever dreamed was possible.
I think of Lockie often when I ride, mostly because of one of his favorite phrases, "Feel it?? Feel it??" He was never quite satisfied until I, as a rider, could honestly reply, "Yes!"
Here's the key. It's one thing to intellectually understand a riding theory, or even to practice an exercise, but until you can feel what's happening and put the theory into practice with results, you haven't really learned to ride. More important, you haven't really learned how to train either. Lockie was a master trainer who'd had to cope with nearly every kind of training issue you might run into with a horse, and he'd apply every one of the lessons he'd learned along the way to the lessons he taught. He didn't want me to just ride, he wanted me to be able to make my horse better.
Even today, I still ride by feel. I never quite figure out how to solve a training problem with a horse until I'm in the saddle, "Feeling it." Sure, there are exercises that work, and some that don't.
I took a lesson on Tucker more recently with a trainer who noticed how he was falling in with his right hind/haunches on the canter--cantering crookedly. Her solution? Ride him in a bit of a shoulder-in at the canter. But, with Tucker, all that did was curl him up into a "C" with his haunches still in. By the second circuit of the arena, I changed tactics on my own, flexing him to the outside--counterbend--to stretch the inside of his body, keeping my right leg a bit behind the girth to push his hind end out. Result? Haunches back where they belonged and the start of a straight canter. He was no longer able to escape through his left shoulder and I had a place to push that right hind leg.
The trainer was quick enough to agree with my solution, but it wasn't one that had ever occurred to her. She was teaching by theory instead of "feel" and simply did not have a big enough "bag of tricks" to offer an alternative when her method didn't correct the problem.
Lockie would have thought of it, and probably added something like, "Oh, and lower your left ear too so you're back on your left seat bone." And then.....
"NOW he's cantering straight. Feel it???"