So invocation together with the glyph now lets mages heal themselves for 20% of their health whenever they want. The channel time is app. 2.65 with haste and crit.
I tested it with a friend, me on ele, him on mage.
I was free casting (no cooldowns) and he was free healing.
Couldn't get him below 80%, since he heals for app. 30k every second and my cast are app. 1.5 seconds.
So we tried something else. How much could he cc me and heal himself for?
Dragons breath: App. 100k heal in that.
Imp CS: App. 80k heal in that.
Sheep: Full heals obviously.