A lot of abilities have a "dealing weapon damage plus x" modifier in there, presumably to make stuff scale with gear. What I'm curious about, however, is which weapon is used when calculating this additional damage.
I did some testing on my Bard with a bow (7-14 damage) in the ranged slot, an axe (5-9 damage) in the main hand slot and a dagger (3-6 damage) in the off-hand slot. What I noticed was that regardless of which weapon was equipped (bow + melee, bow w/o melee and melee w/o bow), my Cadence did the same amount of damage.
As such, I have no idea what to conclude. Does it pick the best weapon equipped and go with that one? Does it use the ranged weapon if you're out of melee range and the melee weapons if you're not? What about an ability that can be used at range as well as in melee?
Ps. I tried looking through the official forums and the wiki, but came up short.