Sure, helping offtank is one thing, running around like an idiot thinking you can do what you want is the issue tho. As a healer I have seen FAR to many people thinking they are a one man army. Im also getting irritated with the people using their most powerfull area of effect weapons after I and other group members crowed control things. Im going to just start letting those ******* die.
Yeah, I've watched too many squishies pull aggro, then claim they are "offtanking" something while I'm trying to heal their cloth covered butts back up. Trust me, I've played a healer often enough to know the difference between keeping a mob off my back and trying to cover up your own mistakes. Part of good offtanking is also knowing when it's a good time to let the regular tank pick things back up. Although, dying does tend to solve that, lol.
I've only really been doing flashpoints in groups with RL friends, how often are people using target markers in instances?