Now in PvP, since expertise healing bonus is technically trauma ignore, not throughput bonus I'm assuming that expertise doesn't affect the amount of absorb that a bubble has.

so you get a nice simple equation to plug your own toon's stats into.

Bubble = {3.27 * [0.14(CasterWP) + 0.17(CasterFP) + 0.17(CasterP)] + 0.164(7085)} + 20 * {1 - [ 1 - ( 0.01 / 0.2 ) ]^[( TargetExpertise / 50 ) / 0.72 ] }

Then why is TargetExpertise in the equation?