For my math I was assuming very low gear levels, as in just hit 70, then bought the Evoker PVP gear to update any old greens (~10G a piece, honored rep rewards, very reasonable to have as soon as you ding 70 IMO)
For a comparison,
my mage has ~600 damage in PVP gear (I know it's not very good), so in my case, with my spec, I average about 1764 with trinkets, or 1560 without, and I'm not specc'd for max damage.
PS That calculation is based on no resistance, and PVE - no resilience. I also chose a really easy gear level to get, to show that it's really about the spec, not the gear.