What are the parse numbers on a bard with WM and without?

[Wintersandman]

Using WM actually isn't that big of a DPS increase at all- and this is ignoring mechanics interrupting the casting during WM.

It's a 12% increase in Damage. I call that pretty significant, especially in a long fight. That would theoretically be 50,000 damage missed over the course of the fight like the A/F3 fight that was shown.