Coming from an Mist of Pandaria pplayer (main playing houres) i have al 4 expantions on my PC , so i kind move through the day betwen them. Only problem is the Woltk Icecrown , que... so when i see the que i just stick to , MOp, BC, Cataclysm.
If everyone did the same, there will be no Que and all realms populated. Job done!