Twice tonight (both times in Shattered Halls) I was accused of using Feign Death too much. Both were by other Hunters. Both other Hunters seemed (imo) to be either functionally clueless or exceptionally selfish in the team play department. Nevertheless, I just want to run a few scenarios by ya'll where I normally FD.
1) Mob(s) on me at melee range with traps on cooldown. Basic self defense...I can't CC or dps if I'm dead, and Deterence can only get me out of so much trouble. Drop threat, get to range and see where the mobs go...if necessary pull them back off of clothies and kite until other options are available.
2) Closing in on tank's threat level. FD to reset threat and resume firing. Pretty straightforward stuff...usually reserved for boss fights or those nasty uber-elites roaming the various level 70 dungeons in Outland. If it's got more than 20-25k HP or I get a few lucky crits off at the start, FD keeps the mobs where they should be, saves on healer mana (and threat), and keeps me in the game to continue fighting at as close to peak dps as I can manage.
3) Healer and tank down, more mobs flailing around than could possibly be downed before a wipe. Saves time. Sometimes it just becomes fantastically apparent that you're in a no win situation and FD saves a corpse run/rez timer. If it looks like a mob or two can be downed before the wipe, I'll stay up and do my best to clear them so we don't have to fight them again, but as soon as one of them turns on me and I'm out of sneaky tricks to keep them at range, I FD and stay down until it's over. I've stuck around long enough to yank a seemingly hopeless situation out of the fire in the past...I wouldn't say I give up to easily. Sometimes you just need to know when to cut your losses and try again.