Thank you! It’s definitely enlightening to go through!
You’re 100% correct. The instructor judges were pretty adamant about not rewarding front to back riding as it completely undermines the training scale and does not prepare horse or rider to go up the levels. In addition to being incorrect riding, it’s very expensive from a points perspective.
When we went through full tests it got penalized on both the movement itself and in the collective marks. For collectives it impacted Impulsion and Rider’s Correct and Effective Use of Aids, but also potentially in Submission if the horse took offense to the riders’ hands. It generally was the thing they chose to focus on in their final remarks as well when it was seen.
They would much, much rather see a horse moving forward steadily into the contact from behind than being pulled onto the vertical.