Put Vital Interfere at 12 if you want to spam vi ls vi bs out of combo, but you shouldn't (for lazy dungeon farmers only). I keep it at 20 now, along with Storm grind (its fine at 20) and force kick (cause I like the damage). Lightning Slash can go to 12, but you lose flexibility in combos (I keep it at 9 now). And please take note that Concentration is not in the list, bladers don't need it.