It is most definitely NOT a glass cannon class. It makes others hit significantly harder in something like a raid group, but it does average damage over all.
I can do some high opening burst, but when things settle my damage is going to even out much lower. The dragoon, or black mage I have as a partner though, they are going to be doing amazing - or at least they should be, if they know how to play. Now if we are talking about the current state of machinist, that can be a glass cannon physical ranged dps.