Sure. As I think I made clear, I would have little confidence in McCain's willingness to reliably do the right thing in any given situation. (Taking it as read for the moment that agreeing to bring Guantanamo detainees to the US would be the right thing at this point.) But with the combination of stronger external pressure, (maybe) more cooperative Congressional Republicans, and whatever McCain might have felt like doing once President, it seems possible (very far from assured) that he might have made more progress down the military-tribunals route than Obama has made down either that or the US-trials route. (It would be harder to see McCain reversing his consistent opposition to US trials for the detainees.) The strongest reason to think otherwise would seem to be scepticism that anyone could really make the military-tribunal option work efficiently.