I just want to point out this can actually be a very bad thing, because of how Regen generates hate - not only does it generate a surprisingly large amount of it, every tick of HP it restores on the target it actually is sending the hate created back onto
you the healer, so if you cast it before the tank pulls it can actually backfire in causing the enemy to ignore the tank completely and start munching on you instead, which can be compounded even more with normal healing and DPSing.
So it usually pays to hold off casting it on the tank until
after they've pulled and built up initial hate first to stop getting too much hate on you right off the bat. I found this out the hard way numerous times levelling WHM and finding Regen was doing more harm than good when cast prior to pulling (which in FFXI was a perfectly valid strategy). A lot of WHMs are not aware of this though so please don't feel bad about it!
