I had this once (or, I imagine it was like this not long before I came in) -- joining an in-progress Brayflox on the last boss, the first thing the tank said was along the lines of "PLEASE tell me you know what Esuna is!"
And, since that might be more of a horror story, here's another confession: I had my first case of nearly letting a tank die because I was in the chat box. I type faster than most, I think, but I'm obsessed with writing (and proofreading) complete sentences, so it can still take me 4-6 seconds to write something fairly short. This isn't always good when the tank's just pulled a group of four. -.-