Sterge
Premium Platinum
But if he rode Vuelta or Giro wouldn't he feasibly be the team leader? Sky could give the Giro to Porte, Le Tour to Wiggins and the Vuelta to Porte, or some combination therein.
I vaguely remember the commentators mentioning during one of the early stages that Porte only signed on again with sky because they promised him the team lead in next years giro