I posted weeks ago that I felt multiboxing would be useful in this game, even if you only boxed a tank/healer for the exact situation
that you mention. What if you were solo and wanted to quest in that zone? Who is going to help you close the rift and clear the
elites from the quest hubs? You certainly cannot do that playing solo.

When RIFT goes retail and everyone is leveling up the game will be great, but if they can't keep the player base and the lower
level zones populated well... then what will new players do? Or people leveling alts?