yeah we really don't know how the accelerated aging works, but solid snake went from nearly his normal age in looks in mgs2 to that of a 60+ year old man in mgs4. it's safe to say that the majority of the acceleration takes place later, at least for solid and liquid. eli is another piece of evidence of that, he's 12 and he looks 12. so solidus could hypothetically age faster than the other 2, but we really don't have much evidence to support that. plus, 8 year old solidus looks like 49 year old big boss? ehhhhh. solidus being someone like the medic would be at least a little big more plausible. still, like the last few mgs games, fans are obsessed with the main character being someone else and/or the game being some kind of VR simulation. time and time again people have come up with these theories post mgs2 and time and time again we've gotten the game, setting, and main character that was presented to us in trailers.