Is there some unspoken rule to not use Esuna/Leech?

[Vrankyl]

I always use Leeches when I can, and like many other healers I follow a tier. Healers first, then tank, and then dps. There are also many other factors that go into it such as if it is about to fall off anyway I am not going to waste my time, my mp, and your time to even bother removing it because at that point it really is pointless. or for poisons as others say that get reapplied like in WP HM with the slimes.
The only other times I don't use Leeches is if you are a moron and always getting caught in avoidable aoe (especially Morbol's), or if you are the idiot who decided to pull two rooms worth of stuff and use berserk and then proceed to not use any defensive cool downs and then start pestering me by spamming your stupid pacification macro until pacification is gone when I am obviously WAY too busy trying to keep you alive because again you didn't use cool downs. Btw normally I have no problem with the macro it is a nice heads up, but please for the love of all don't spam it.

Any other time that Leeches/Esuna isn't use when it can't be, well someone is doing it wrong. *cough*WoD*cough*