At what point do you give up?

[Sprat]

That is because his muscles haven't yet developed enough for him to allow him to carry himself properly. A strong contact isn't going to help that, which your RI should know! Before selling the horse, I would find a good instructor. I know you like this one but s/he honestly doesn't sound very knowledgeable.

It must be something about riding instructors around my area - the last 3 that I have had have all said the same thing!

 

[Myloubylou]

Was through master dressage, was a free webinar which Demo's content from the book. Not sure if can watch without getting book

 

[LilacWillow]

Depends. What do you want to achieve?
Maybe have some more realistic goals? Perhaps you are expecting too much?
Appreciate your horse for what he is, not who you want him to be?

 

[FfionWinnie]

If the contact issue is the only problem then agree get another instructor! My Welsh D was at times a moron and very stiff, leaned on one side, leaned on both reins, chucked her head around, you name it, due to bad riding before I bought her. It really hasn't taken much better for me to sort this out but I have managed it due to having a good instructor. They can only lean if you let them. Sounds simple and it is simple but you need the right help.

My mare still has a long way to go in her schooling but the unpleasant head behaviour is cured.