Monks don't have a self heal...
Beastmaster is centered around high HP and self heals though, it's not very realistic to say that should be the standard for all tanks... In that case, my bear wants a HUGE defense increase, because then I guess knight sets the standard for that.
Both Warriors (Tension Relax) and BMs (Survival) follow that pattern, though. I was simply pointing out that in order for Aura Heal to keep up with the other two tank heals, it would need to heal 10% of your HP. Since it is highly unlikely to (especially if you aren't fully DPS specced), it is arguably the worst tank self-heal aside from Monk's (non-existent) heal.
I'm just saying that the healing doesn't seem worth the investment, since you essentially end up with a bad Rejuvenation on a much longer cooldown. While you can use it to throw a heal at someone else, there are other classes much better suited for that, and it doesn't seem like it is going to save you enough Potions while soloing to justify taking points out of other Skills.
As an aside, I wouldn't be surprised if BMs get a significant defense increase at some point (50% => 75%~100% on Grizzly seems most likely). While they certainly have the best HP in the game, their low mitigation makes them the hardest tank to heal.