To put this into context, our White Mage in our Static, who we've been clearing Coil with for months now, only realised this week that the glowing panels during the Cad fight in Turn 1 spawned the Slimes :P 'I was wondering why the Bards start randomly taking damage...'

I'm in agreement with the OP to some extent, having now played every Dungeon and fight on my Tank and DPS (with the exception of Coil), and the majority on my White Mage. But just because you're a DPS doesn't just make you know the fight more. I just think each role learns the mechanics which are more relevant to them, but if a DPS learns the full mechanics, then great, but it doesn't make you a bad DPS by not knowing how EVERYTHING works either.

Titan XM as an example, on my Monk, all I need to do is avoid the AOE, kill the adds and kill Titan, while maintaining my stacks of GL, and as long as I can avoid stuff, the pattern isn't so important. As a Tank I need to know the pattern in order to pre-buff for Mountain Busters and when to tank switch, how to grab the adds, etc.