The enhancement on the DNC AF3 body gives striking flourish a chance to force a crit that will work on WS, despite the fact that the actual crit flourish (climactic) doesn't work on non-crit WS, for all the sense that makes.
The issue is striking is on a 2 min timer, so at best you'd be using it with Rudras when the recast is up for the chance at a crit and some aftermath while using Evis the rest of the time. At the very least Twashtar's DEX and high base damage make it a good mainhand dagger for DNC to Evis with anyway.
Whether alternating Striking+Rudras/Evis and the damage from the temporary aftermath is worth the trouble compared to just spamming Evis can only be determined if you know just how high the chance of crit is for Striking and what kind of damage it can reliably do.
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