I always play symmetrically and see N+1k maps as training wheels. I treat 7+1k maps as 8k, there is no difference to me other than less keys to hit on one side or play to the tune of the instrument. I don't see how that is a problem unless you play on multiplayer, whereas in single you can just go through the map once to see if it's N+1k or not. I'm neutral on this idea.