So, I'm looking at this skill... and I don't see it's point. Compare it to the True / Vorpal combo you already have by the time you learn the skill. Two hits, and you've done 350 damage instead of 360, and spent 130 TP instead of 140 TP. Very slightly more damage, for slightly more TP. Not exactly exciting, but probably worth it if you're tank is semi-competant.

But when you get Full Thrust, it goes out the window. In three hits, you've done 650 damage for 190 TP instead of 540 for 210 TP. Significantly less damage for a bit more TP. As such, Impulse Drive seems very situational. Sure, if you can't score in three hits in a row without needing to use some other Weaponskill that would interupt the chain, it's better, but you only need to have two dedicated attacks in a row to perform the True / Vorpal combo which is roughly equivalent, and may set you up for MUCH more damage.

Am I simply missing something here?