So it's good for Glass Cannon builds? Ok, that makes sense.
To be fair, there aren't that many Scoundrel skills that are better than Fast track (with the exception of Walk in Shadows, Cloak and Dagger or any CC abilities). For example: Daggers Drawn, Lacerate, and Venomous Strike. Daggers Drawn is terrible because it scales with nothing. Daggers Drawn doesn't count as backstabbing even if your positioning is perfect and it isn't modified by Guerrilla if you're sneaking (you could do more damage with 2 backstabs for just 4 AP than you would do with Daggers Drawn for 8 AP, which is ridiculous). Lacerate and Venomous Strike deal pathetic damage relative to their cost. You'd be better off spending the AP on just sneaking then backstabbing (or CC to keep your target locked down).