Alright well most everyone knows about Cloud and his real deal with SOLDIER. This may give a bit away so I will put it in spoiler tags.
Anyone disagree or have anything to add?
Cloud really wasn't in SOLDIER, he was really just a low guard that had Zack's memories infused into his brain. He didn't know that, so he thought he really was an EX-SOLDIER. Thinking he was one of them, he performed like one of them. You saw him in the beggining, he was performing missions like it was nothing, and he was beyond the skills of most of your teamates. So really, Cloud performed as an EX-SOLDIER even though he really wasn't because he thought he was.