Yellow line burg's other corruption removal is Startling Twist. It's aoe, it stuns, and its cooldown can be reduced 2s every time you use Subtle Stab. Only every 25+ seconds as opposed to Purge Corruption's 15s cooldown, but if you're using SS off cooldown for the Glee healing cooldown too, it's not bad, and doesn't require a crit at least.
Frisco addressed this pretty well already. Burglars currently have more reliable access to corruption removal than many other classes. You can initiate a fight by using a nondamaging trick, follow it with Startling Twist, and remove a corruption without ever dealing damage, let alone needing a critical hit.
The burglar has numerous key skills which are tied to its crit chain and are otherwise unavailable. This is not a bug, and in general it improves the speed at which you can remove corruptions while Startling Twist is on cooldown.