I think she's just a little upset because she's asking about her horse's jumping style, not her riding. And she probably knows that her position will probably affect the horse's jump, but as she said these are old videos and she may have improved since then.
I know belive me I know not releasing will affect oscars jump. I have changed and have put a plait in oscars mane and I reach for the plait going over a jump.
I havent always been like that I just took two bad falls in february which totally knocked my confidence and I nearly gave up jumping altogether