Inner Fire Sucks

I once took a 2000 mainhand mutilate crit. True story. I'll never know how much the offhand would've done because it never landed. I died faster than he could move his other hand.
In retrospect, the number is slightly skewed because my inner fire wore off during his kidney shot, and the kidney shot was probably improved (9% more damage), but still.
That alone is one of my issues with inner fire. It is the only buff in the game that wears off when you really need it. It's like, you're getting hit very hard and very fast, your raid leader is yelling for more dots, and Boom! Your protection fades from you. Ridiculous. What's a priest gotta do to get some reliable protection around here?
This is probably redundant but I think this is a fair analogy: having inner fire is like going into a big bar fight with a night elf rogue for backup, because you know those pointy-eared cowards are going to vanish once the taurens get drunk. You'd be like, Hey, Legollas, get the guy who's punching me in the -- Poof! Gone.
The rest of the time inner fire just sort of sticks around. Like when you're sitting in Shattrath and it's physically impossible to get ganked, inner fire will stay with you for... 10 minutes. Now, mage armor will regen your mana while casting for 30 minutes, fel armor will increase your healing effects and spell damage for 30 minutes, but inner fire will give you some unreliable armor for... 10 minutes.