Viable in PvP, depends.
- Extremely effective against baddies (they dont know how to deal with CC).
- Moderately effective against PUG's, dissarray and lack of coordination give you enough to slip death.
- Horrible against premades and any team composition. The coordination by premades ensures you will be permanently rooted. It only takes 8 seconds from a competent warrior, powertech or Juggernaught to lay on the hurt in a way you cannot recover.
Pretty good summary here. Sorc DPS is hella fun and you can (with reasonable skill) put up decent numbers in unranked warzone competitions. Which is all I play in so I mean, I just roll with that.
Just at the highest end, it just doesn't hang with other DPS specs. If anyone was legitimately good enough to take a DPS sorc to a rated, then it'd be argued he'd be far better served levelign a more powerful alt and doing 30-50% more damage in the same scenario.