Again, I would refer to Dick Fosbury. How much push back was there for him when he went backwards over the bar? If there was, then how long did it last after he started jumping higher than everybody else?
My two cents: if the technique allows another route for people to have success and push distances farther, without putting people in danger (a la rotational javelin),and while staying within the framework of the rules, then go for it.
Jeremy Hammond Essex High School Essex Junction, VT