Probably already know, but it's spamming cancel spell a lot..
/cancel Regrowth on Warrior @ 81.7%
41:792 - Lifebloom on Warrior at 95 % hp
43:077 - Regrowth on Druid at 79 % hp
/cancel Regrowth on Druid @ 78.7%
43:607 - Regrowth on Druid at 79 % hp
/cancel Regrowth on Druid @ 80.0%
44:031 - Regrowth on Druid at 80 % hp
/cancel Regrowth on Druid @ 80.0%
44:581 - Rejuvenation on Druid at 81 % hp
45:539 - Regrowth on Warrior at 68 % hp
/cancel Regrowth on Warrior @ 52.4%
46:142 - Regrowth on Warrior at 52 % hp
/cancel Regrowth on Warrior @ 52.4%
46:590 - Regrowth on Warrior at 52 % hp
/cancel Regrowth on Warrior @ 52.4%
47:106 - Regrowth on Paladin at 55 % hp
/cancel Regrowth on Paladin @ 55.4%
47:686 - Regrowth on Paladin at 55 % hp
/cancel Regrowth on Paladin @ 55.4%
48:111 - Regrowth on Paladin at 55 % hp
/cancel Regrowth on Paladin @ 55.4%
48:548 - Regrowth on Warrior at 55 % hp
/cancel Regrowth on Warrior @ 54.5%
49:014 - Regrowth on Warrior at 55 % hp
/cancel Regrowth on Warrior @ 54.5%
49:491 - Regrowth on Warrior at 55 % hp
/cancel Regrowth on Warrior @ 48.3%
49:913 - Regrowth on Warrior at 48 % hp
/cancel Regrowth on Warrior @ 48.3%
50:361 - Wild Growth on Rogue at 78 % hp
.. even when they're low HP.
'Gara'jal the Spiritbinder' - I'm #1