My three year old is slightly long in the back and short in the neck. I want to do some dressage on her in a year or two. How will these conformation faults affect her performance/??
The long back will make it harder for her to engage. The short neck will make it hard to push her up, over and in front of you with the nose taking the bit forward as to the eye, she will always look tighter in the neck.
It really depends on the severity of the faults. If your horse is only very slightly long in the back/short necked, then it shouldn't be much of a problem.