There is no way Wiggins would have been "shelled out the back" if he had the same form as last year.
Assuming Wiggins was also sat behind Porte (like Froome was able to last year) then he would have probably been 2nd or 3rd on the stage. He wouldn't have been able to stay with Froomes acceleration but he would have probably lost less than a minute. Ventoux is steep but is not Giro/Vuelta steep and its long so it suits Wiggins "TT to the top" style on the climb. As a reference last year Wiggins beat Nibali in the mountains and he is widely regarded as the second best rider at the moment after Froome, he is also the only rider to beat Froome is a stage race this year.
A moot point maybe and I'm prepared to accept that you may be right but if Wiggins had been playing the domestique role he may well have had to bury himself a la Kennaugh and Porte in order to launch Froome to victory. In that case no way would he have been steadily cruising up the climb in the same group as Contador etc.
Richie Porte finished 2:49 back from Froome and had obviously learned his lesson from stage 8 where he went too hard instead of easing off and saving himself for future support duties.
It may well have been of course that Wiggins would have been a lot further up the GC due to his performance in the time trial so Sky may well have been hedging their bets to have Wiggins in reserve just in case Froome got in to trouble.
Don't get me wrong I am a Wiggins fan, I just don't think it would have been anywhere near like last year with the roles reversed as the circumstances are completely different.