The stewards' assumption seems to be that the top guys are so good, it must be the unavoidable fault of the horse when interference occurs. WH is saying they commit a professional foul because they think they will get away with it. Assumption no1 may very conceivably be fuelling behaviour no2.

I feel jockeys don't need to be "understood", only horses. If the stewards have a working knowledge of how a horse may behave and what a competent jockey should do to correct it, that is sufficient. Riders ride to the way the rules are "refereed." Be stricter, they will change their habits.