Did a little test while doing ifrit

members of my fc, pretty geared - not the top, but nice - the 3 of us with an ifrit weapon equipped, against ifrit

BLM - 177 dps (counting lb3)
DRG - 163 (counting lb3)
BRD - 134 (counting -20%dmg for mage's ballad)

The absence of a DPS LB is an obvious reduction on the overall dps, and the songs using too is another reduction. Still, i can suggest that "morally" we Bard are pretty strong as DPS.