Well, I stand corrected. Obviously if you can taxi a Cessna 152 or 172, line it up on the runway, or take off then you can fly any airplane in real life. Shoot, a Viper would be EASY! You don't have to worry about torque or P-factor in a jet! I'm sure in your vast experience of ONE time in a real plane, coupled with your X hours in computer sims, you could execute a simple training mission in a single seat, high performance fighter jet.

There is more to flying than making the trees smaller, a lot more. "Flying" involves several things; the basics are "Aviate, Navigate, Communicate". As some of you said, landing might be difficult. That's part of aviating. If you can't do it, you can't "fly". You are simply delaying your crash. Flying around in a "real" sim, but not being able to find your way back to an airport is a lack of Navigation. The result would be you run out of gas and crash. I haven't heard anyone say anything about talking on the radios. Communication. At a controlled airport (such as a military field where a Viper would be), you wouldn't even be allowed to taxi if you couldn't communicate with the right personnel. In some cases, you wouldn't even be allowed to start the engine without permission. Not going flying there.
Would your sim experience give you a leg up on someone with no experience even close to flying? Possibly. If you learned how to properly operate the equipment on board, and developed good flying habits then yea, I'd say you have a slight edge.
That doesn't mean that you could jump from a sim into a Viper and be just hunky-dorey! Get over you illusions of grandeur! You would still have to get some real life training before you jump in the seat all by yourself.
Oh, and have a nice day!
