This has all been discussed before. In order to beat Fedor, you have to be able to do at least one of the following things. And we're not even talking about Prime Fedor here but Out Of Prime Fedor:
- Out-mass him (like Bigfoot, who was supposedly 280+ on fight night)
- Hurt him with power (Hendo, Maldonado)
- Trick him and have superior subs (Werdum, who is the master at this as shown in Cain fight)
Jones doesn't have these qualities. He's not big enough, he doesn't hit hard enough, and his subs aren't good enough.
What this means is that Fedor would go right at Jones with no fear at all. And if you can't slow down Fedor he will run through you like a hot knife through butter. Fedor has done this to men larger than Jones.
Jones is a heck of a fighter. But he's built on height and reach (and apparently roids). Fedor isn't. This is why there are no "Gus fights" in Fedor's prime. There was no time in Fedor's prime when he was 'exposed' because someone turned up who had similar height as reach as him. And so forth.
Jones is a great fighter. He is. But he's no Fedor and he would get wrecked by Prime Fedor head to head. As I said, I think a Brett Rogers or Tim Sylvia obliteration would probably be Jones' fate if he stepped in the ring/cage with Prime Fedor.
It would be brutal, and it would be a short fight. Jones would have no idea what happened to him.