I wasn't there, and I didn't see and hear the lesson, but from the way you described it, I don't have a problem with what was being taught.
It sounds like a low intermediate lesson, where the students have mastered basic design of position but not advanced aids. What was taught, and I hope still is taught, in hunters, is that the best round is the one in which that rider does as little as possible. If you've done your homework; and you pick up the correct pace and balance in your hunter circle, you should be able to ride the entire course from two point only providing your horse with steering cues - pace and balance were established in the hunter circle.
My choice of words there was deliberate; because every XC clinic I attended (including Wofford, Karen Lende O'Connor, Lucinda Prior-Palmer Green and others) and every eventing instructor I ever listened to emphasized similiar basics - the *horse* is responsible for the "spot" or distance; the rider is only responsible for pace, balance and direction. Everything else is the horse's job. So why is instructing low intermediates to sit still and do nothing an issue? Were these riders at a level where they could see a different distance coming out of the corner and move up to it? From your description I think not.
Also, I found this comment to be telling:
They were riding around without using their seats
Yes, because that's correct for hunters. Hunter seat riders only use their weight for an aid, opening and closing their hip angle. Using your seat is incorrect on a hunter. Now, I know that seems strange to an event rider, to give up that all important seat aid, but a hunter should shorten and lengthen, and even change balance, according to the hip angle and position of the upper body.
Now get ready for a big shock: back in the day, when GM and I were both young(er), you could show hunters and hunter seat eq successfully without *ever* sitting the canter. AND I remember people complaining about "all this d*** belly dancing" and sitting on the horse's back like that ruining a good hunter.
In addition, something I was taught, and taught to my students, was *never* to make an adjustment or change in pace, balance or direction closer than three strides out from a fence; at closer than three strides out, the horse can no longer clearly see the fence or judge distance, so if you interfere with him, your "eye" better be darn good.
The old Litteaur training sequence for teaching hunter or forward seat riding, which I still stand by, is as follows: elementary level - the goal is authority over the horse, with non-interference of the horse's natural movement. Riders ride on loose reins, and concentrate on the correct sequence of the aids. Elementary level riders jump, and jump low courses, on loose reins, in two point, grabbing mane for their release. The goal of intermediate riding is passive following, or learning to be a good passenger. Principles of following seat and passive, following hand are introduced. Low intermediates jump courses keeping contact around the turns, and using elementary release techinique (hands forward three strides ahead.) High intermediates have perfected passive, following contact and use a crest release. The goal of an advanced rider is invisible aids, subtly and positively influencing the horses' way of going. Advanced riders use active aids, within the horses natural rhythm, to influence the horses' way of going and use an automatic release over fences.
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