Yeh it certainly is. I know he did a lot of work for froome at the start and helped get him to where he is now but wtf happened there.
That’s just how it works when supporting a GC rider. Ride hard as long as you can and when your job is done you peel off and soft pedal what’s left to conserve as much energy as possible. Porte’s position on GC is pretty irrelevant to the team. Being as fresh as possible for the next day is vital.
His position on GC is more a reflection of team tactics than capability.
Can also be advantageous to be low on GC as they can send him up the road to support Froome later in a stage and no one is going to chase.
(Also seem to remember reading he had some bug too. Or was that Roche?)