"I soloed Clamstok as a level 90 i450 enhancement shaman.
Drop your Fire Elemental Totem and use Ascendance (and Berserk, if you're troll), but do not immediately use your Feral Spirits CD. Once the Ascendance duration ends, drop Healing Stream Totem, Capacitor Totem, and use Flame Shock & immediately activate Bloodlust. Profit.Also, I timed Clamstok's spawn cooldown. Seems you only have to wait several minutes at most."
(This monster does not drop Lobstmourne; see Clawlord Kril'mandar.)