Originally Posted by
Yelsha
Sorry, no data for you. But the only skills where I noticed break having an effect is on Thousand Strikes, Horns of Hell, and Flamewall. You can test it yourself, just make sure your break rating is higher than the opponents block rating. If their block is sufficiently high, then break will not increase your damage on those skills either. This is why mages take much more damage from Thousand Strikes in comparison to other skills, because they do not benefit from block rating.
A corollary is that block reduces damage from Thousand Strikes, Horns of Hell, and Flamewall. The exact mechanics and ratios and numbers involved, I have no idea. But you can run some simple tests to confirm the general observations.