Originally Posted by
Fae
Improved Sprint and Killing Spree help quite a bit for mobility tho. Both work as gap closers AND unlike Shadowstep, break roots. It also has a bit more CC instead of mobility so you don't get kited so easily. I think that one of the biggest strengths is 6 second gouge that allows cheap restealths. So you can actually get more openings than Subtlety with Vanish and Preparation.
But as I said, it's really mainly for duels and battlegrouns, mainly because Preparation isn't used much there. For "blow all your cooldowns in 4 minutes" arenas, Subtlety clearly wins.