I've met a number of ignorant healers and others who refuse to use such abilities in PVP. They seem to be forgetting something very important, regardless of whether or not the defense applies.

Pop quiz: What do Wither, Glory Slash, One Ilm Punch, and numerous other abilities have in common?

There are abilities out there that dispel your buffs. Having a useless buff up to filter the dispel and keep your other important buffs up is pretty good. If you're a healer and you're too stubborn to take two seconds to prepare your team before battle, you probably shouldn't be doing PVP.

Always keep those buffs up to help your party out and filter out the crippling dispel attacks.