Avoid this mistake with your alts in Mists of Pandaria: Timerunning! 

World of Warcraft: Mists of Pandaria Timerunning is out, and I want to make sure you're aware of this idiosyncrasy in how your Cloak buff is shared between characters before potentially wasting time!
Starting values for alts:
Infinite Power X: 16% increased exp gain
Infinite Power XI: 50% increased exp gain
Infinite Power XII: 100% increased exp gain