T13 adds

[SpookyGhost]

I would just like to point out that the idea that using an Off GCD attack after your GCD shortens the time before it takes effect is wrong.

Though animation cancelling has been disproved, using Brutal Swing after OP/SS/BB will get you quicker snap aggro due to the damage of BS registering quickly (especially for BB).

Yeah, pointed that out. SS is better in general, though BB is higher single GCD snap aggro if necessary and you have BS available. For Shadows I think OP or SS is best, it's honestly not too big of a deal which you use. Flash works, apparently, though if the GCD for Flash is still ticking once you're able to target the Shadow then you've got a bit of a problem in terms of damage/enmity generated... but we're nearing the end of 2.5 so do whatever works lol