Mr. Smiley
Member
I think that's just part of the retcon. I don't believe Ocelot was supposed to be "faking" during MGS2; as far as Kojima was concerned he was almost certainly being possessed by Liquid back then. MGS4 changed things up and so Liquid's voice was excised. (I'm not so sure the MGS database explanation that Ocelot was actually possessed in MGS2 and then faked it for MGS4 is something that the game's writers even had in mind, honestly. But who knows.)
It sounds like he did. Maybe I'm mistaken though.
IIRC, Ocelot's english voice actor voiced the Liquid parts in the MGS2 motion comic which came out before MGS4. I think that's where the "voice retcon" originated, kinda-sorta-not really like the removal of the character accents in Twin Snakes which carried over to MGS4.