I read a while back about the weather paterns as clues to the games acts.
Well, what if this dude is not Big Boss, but another Big Boss clone.
Hidden Sun, not meaning snakes infiltraion, but a hidden Snake clone.
I like the idea. Hidden Snake. Sounds catchy.
Also, with it looking like this 'Snake' is a Mercenary, it could mean squad based sneaking, maybe solo-sneaking. But imagine multiplayer sneaking, that would be epic as to all the stuff you could do. One dude acts as decoy, the other coming up and taking out the soliders from the behind.
Epic.