- Three things dramatically reduce threat generation for any tank, whether their class was intended to tank or not: misses, dodges and parries. Misses are counterbalanced by Hit Rating; dodges & parries are counterbalanced by Expertise.
- Mend Pet can be used to generate additional threat by way of healer aggro.
- Mana Potions, Healing Potions and Healthstones all generate threat equivalent to the amount of health/mana returned. Also, use of Fel Mana Potions is probably your best angle here, since it returns mana over time and gives a guaranteed 3200 mana. Additionally, since hunter mechanics don't work off of spell damage, there is no drawback to these potions.
The observation about Fel Mana Potions is simply brilliant. With a healer behind me, it's fairly safe to consume these instead of healing potions, and they don't cause me to suffer an important stat reduction in the way a Fel Regeneration Potion would. In practical terms, a Fel Mana Potion is like a bottle of Liquid Threat (base threat is 0.5x Mana gained). WoWWiki spells it out in their post on Threat:
Threat caused by beneficial effects is divided amongst all NPCs that are aware of the character. This global threat applies to heals, bonus threat from buffs (such as Battle Shout or Arcane Brilliance), and power gains (such as a Mana Potion or Rage Potion).
What's more, the observation about healer aggro positively shamed me. I should have been far more conscious of that. I've mentioned before that I also play a druid. In fact, Gweryc is the first character I've ever really played that wasn't a healer. As many times as I've yelled at my computer screen, fists pumping and voice quavering with nerd rage about tanks that don't understand what healing aggro is -- how could I have overlooked that? I may have been aware of it, but I never considered that it might be exploitable.
This concept is enough to make me reconsider my entire combat strategy and even my spec. Given a patient enough team and a pet trained in Cower, I should be able to send in Cafall first and let him take some damage, then pick up the "bonus threat" from Mend Pet while I immediately take aggro off Cafall with a Raptor Strike or an Explosive Trap. I will absolutely be playing with this idea, and if I can work out how to reliably exploit it, I may even respec into Improved Mend Pet.