by Momoh » Tue Jun 09, 2015 8:26 am
It's not a bug, you just need to time your evocation correctly with your mana regen ticks.
Get an addon that tracks when you get your mana ticks (CT_Tickmod). This should enable you to time your evocation just before a mana tick and will help you to never miss your full 4-tick evocations.
Melodyx