So you worry about sandbagging Legends? I'd think that there are more in the lower tiers(?)
Talking about numbers, Legends must play a minimum of 500 rounds to advance. Thus, after 500 really good scores in RGs, any Legend would probably be promoted. OTOH, there are Legends (like me) who will never contend in an RG and will never advance to TL on their own. Should they be pushed up after ?1,000? rounds without showing any capacity?
BTW, I oppose to the following underlined assumption:
Dubfore: instead of just relying on players scoring average (which we all know can be kept artifically high)
I for one know better, as the average will only react to good scores after saturation - you can only keep it high by NOT playing any good scores (and NOT excelling in RGs).
May I suggest that you try to improve your game if you want success in these?