...Instead of using core and thigh strength to achieve 2 point, they end up just standing in their stirrups. That’s not going to get a good canter seat...
That is how VS Littauer, Harry Chamberlin and "The American Military Seat" taught two point: stand in your stirrups. If you 'stand in your stirrups', your knee (and ankle) acts as hinges to reduce peak impacts on the horse's back. If you two point using "thigh strength", you lose those hinges and reduce the effectiveness of two point in saving the horse's back.
I agree with the others - riding in the correct 2 point position is hard....All lesson riders are taught to canter by sitting back on their pockets...
Riding in two point - when standing in the stirrups - is about balance, not strength. Correct two point position - again, as was long taught in the USA & the US Cavalry - has the rider lean forward enough to center his balance over the stirrups, and then stand in them, letting the legs bend to absorb shock. The entire POINT of two point is to free up the back and reduce peak pressure.
Leaning back makes it easier to keep pressure in the seat. But in a canter, the horse's back needs to rotate up and forward around the horse's withers. By leaning back, you put more weight into the place the horse needs to move more, hampering the horse. Riding with weight in your thighs or leaning back both interfere with what the horse needs to do, and for what? Why would anyone WANT to make cantering harder work for their horse?
Piero Santini's first paragraph on Geometry of the Forward Seat in Riding Reflections (1933):
The verb 'to sit' should be eliminated from our vocabulary where riding is concerned, for the idea it conveys is intrinsically misleading. Were it not for its indecorous connotation the word 'perch' would more aptly suggest the position that the rider should assume in what is commonly described as the 'forward' seat.
. . . the first rule of good riding is that of reducing, simplifying and sometimes, if possible, even eliminating the action of the rider. If the hands are used to turn and check a horse, and the legs to make him move forward and to give him resolution and decisiveness this is enough . . .
If natural work is required of a horse [field work] and not artificial [manege work] he will be better able to make use of his impulses, instincts and his natural balance . . .
. . . the horse who has rational exercise, during which he is allowed to balance himself as he pleases, not being punished with needless suffering, develops in the most efficient fashion, with great advantage to his way of carrying himself, and becomes docile and submissive to the wishes of the rider.
... in order to accustom horses to the field without ruining them and making them bad-tempered, one must always profit by the natural instincts of the animal substantiating his movements and way of going, and one must give him the least possible discomfort in the mouth, loins and ribs. One must abolish the forced position of balance, and any action of the horse's legs beyond that which is essential to move him forward. - Caprilli
Although I'm now mostly a western rider, I believe the early forward seat had a lot going for it. No, I'm not saying this because I've "read it". I'm saying this because I see it again and again in my horses. When I first read "
The French say, when speaking of a horse that shows restiveness, "il se defend" - he defends himself...There is much truth in this expression, and it is one that riders should constantly bear in mind, for insubordination is most commonly the result of something having been demanded from the horse that it either did not know how to do or was unable to perform...", I interpreted it the way it was probably meant: Horses resist when they do not understand cues or what the rider wants them to do.
Increasingly, I think horses spend a lot of time defending themselves and creating mental resistance because standard riding makes the horse work harder than needed to achieve the end, and the horse then resents the riders interference. A horse whose rider is actively trying to help the horse achieve the goal, who is working to HELP the horse, becomes united with his rider. He becomes not just "more docile", but more EAGER to work with his rider.
Even small steps toward reducing how our weight interferes with the horse tells the horse he is being asked to do something rational and that his rider is trying to help him. To be part of a team. And horses, from what I've SEEN, like rational, purposeful exercise:
...There is another thing to be considered with regard to the horse's character - it loves to exercise its powers, and it possesses a great spirit of emulation; it likes variety of scene and amusement; and under a rider that understands how to indulge it in all this without overtaxing its powers, will work willingly to the last gasp, which is what entitles it to the name of a noble and generous animal...
It seems to me this IS basic to how a beginning rider should be taught. We should actively teach new riders based on how they can do the least harm to their horse while riding him, thus encouraging the horse to look forward to being ridden. Riding "in the stirrups" instead of "seat, seat, SEAT" should be taught at the beginning. In part because it is a very easy way to ride. In part because it teaches the rider to appreciate how hard the horse works. And because riding in a half-seat, or perhaps a 3/4 seat, reduces the horse's resistance.
And I find myself having once again to repeat what I said and repeated: the horse will do good work and gladly do so when the cavalryman strives to make his actions less offensive to the horse, and, even though the rider requires that the horse be submissive to his will, leaves the horse freedom in committing its energy and equilibrium...
...For my part I will say that this work has persuaded me more of what I have already said: horses become spoiled and revolt, in general, not as a result of hard work and work that is consistent with their abilities, but rather as the result of painful actions they receive from the rider. - Caprilli
I'm quoting Caprilli, who wrote about teaching beginning riders, because I see the same thing in my horses. There is an excellent translation of Caprilli's longest article on teaching new riders here:
Federico Caprilli, Per L'Equitazione Di Campagna - On Cross Country Riding
PS: An easy way of learning to ride in two point is, oddly enough, in a western saddle. One hand on the slack reins. One hand on the saddle horn until the saddle horn is no longer helpful. Only then use two hands on the reins. And learning bitless helps the horse too.