How thorns (dual blader) works

Since Berserk doubles damage (including crits), Crusher effectively hits 6 times per use. Even though Brandish and Blast are faster, they hit only 2 and 1 times respectively. It'll help all the warriors, but it'll help DrKs the most. And as a sidenote, people really overestimate Heroes. They're not really that great.

And yeah, this'll make Corsairs crazy strong. But that doesn't really matter at all since the Dual Blader will still be much stronger. Seriously, they're broken.

Oh my bad, I assume the crit multiplier is applied before Zerk's 200%, so our benefits should be doubled:
(x + 1.25) * 2 = Thorn-crit damage = 2x + 2.5
(y + 1.25) = y +1.25

Is this correct?

Another question, is Drk's damage with Thorns supposed to be (170% + 125%) * 2 or (100% + 125%) * 1.7 * 2. According to Russt's order of operation, skill modifiers get applied before crit bonuses.