Crysant

So what's the reasoning behind people going for synergy instead of supremacy? Is it because many already have the four piece bonus and don't need the extra fury generated by supremacy?

I'd say the rotation doesn't change much besides maybe the opener, mainly due to the potential proc from Corruption. You will probably still want to sit on one charge and start to use it before the next one is available. I could be wrong for single target though as a 2% chance isn't that much. Will be interesting for aoe though, especially for fights like Darmac or Thogar where you have adds that die to quickly for Doom to tick but still live long enough to get some corruption ticks because it doesn't state only proccing from the latest Corruption. Didn't get to test it yet because I

As far as I know it is not worth delaying DB cycles in hopes of getting a GoSyn proc. Damage numbers do tend to get pretty absurd if the RNG gods reward you though :)

No, it doesn't affect multistrike or critchance. Glyph of shadow bolt has no influence on how the spell works, it is purely cosmetical. That means even if you see three projectiles in the air, those three are treated as if they were only one.