I am not really calling for a nerf, but more of a mechanic fix. The Saboteur is probably the only class in the game with the synergy to 1 shot someone right now. Now take into account that it takes 5 seconds to build up (whippy do), 5 seconds in PvP is nothing. This mechanic seems oddly misplaced. Think about it from a different perspective (the Warrior). Allow him to hit someone 5 times but the damage is actually on reserve instead of over time to allow the healers to react. Now give him a finisher that allows him to apply ALL that damage and the finisher into 1 move; now you have a Warrior based Saboteur. This mechanic works for any class in the game and virtually no healer can anticipate the 1 shot and heal a 2k dmg hit based on 2k health allies/self.
So, now get a 5-10 Man PvP group together with 3 Sab's and the other team has no chance, even a well coordinated team. Below is how the combat would unfold in ventrilo.
Target Caller - Call target (whoever) and gives 1-2 seconds to aquire target for the other 2 Sab's.
Target Caller - Charges out (waits 4 seconds) - basically time to place 4 charges.
---Team places 5 charges each.
Target Caller - Detonate in 3-2-1. BOOM!!!! Dead Target PERIOD!
Target Caller - Next Target (#2) Repeat = The Win easily.
I am fairly certain that this combination of Team will appear because it's inherently overpowered mechanic. This needs to be addressed before it gets abused.