1v1 dark/storm corr?

Combo works but if you want a char that doesn't get hit roll a dark/poison.
With that being said yes, the combo was always decent. With incarnates it makes the endurance cost alot more manageable and allows you to focus your IO slotting in other areas. I would assume however there is good reason you don't see any being used.

Almost anything that duels now focuses on one or 2 components. Either pure dmg, -end, or-tohit, -recharge. Storm is a jack of all trades master of none and requires constant upclose debuffing. It would require alot of finesse.