On RAF i'm not an expert. general rule is idd A -> b b -> c

Then you can grant the same amount of levels on each account.

Boosting is awesome with RAF. It's amazing how fast it goes

especially if you join through LFG and relog on 1 account to the booster and then boost. If you do it correct they get exp as if there wasn't a booster(highlvl) in the group.