The thing about rogues is that if they are sneaking properly, they will *never* get hit. They simply won't be targeted, since enemies don't notice the bush behind them and won't turn around at all unless an attack misses. Of course, things get slightly more complicated when facing big groups of enemies, but that's what Smokescreen is for.

I do agree that the huge cooldowns on their Scoundrel skills that don't lower is a bit unfair though.