I believe that best Del Potro > best Murray, hence the one who wins the match will have the same good chances against Roger, hence the result for Roger is irrelevant.
A good Pony beat Roger in USO. A good Murray couldn't.
The best for Roger though is Murray to beat Pony in 2, which would mean that Pony is in the same terrible form still, as he was in the previous few tournaments.
That would be a relief, as only the mega best Pony has chances to beat Federer right now, while half a Pony is doomed.
Muzza in form or not is a tricky cunning oponent, so he's more likely to bother Fedex wether won or lost Del Potro.
To sum up - if Murray wins, Roger has only one real oponent for the top place in the group (except if it is in third set TB of course).
If Pony wins - Federer is in trouble as he will have 2 serious oponents, both able to beat him and have alrady done it.
My hope - Pony to perform as Nole 2 years ago (lost to everyone or 2 of the 3, don't remember, just as his bad form pre-finale was suggesting).
Also, we shouldn't forget Verdasco as he is becomming a tougher opnent for them all year after year.
If he pulls off an AO 2009 performance, he's gonna mess a lot of calculations.
I hope he does tbh.
Roger and Verdasco through the group and both in the final as well.
That would be a dream come true
And Roger to win it - that would be a bet won