The second fleet wouldn't actually be in the Persian Gulf...that's the Atlantic Fleet, but also operates in the Pacific.
They probably chose it just because it was easy to have a large selection of ships (it's also the largest Fleet).
Either way, a simulation, and a war, are two entirely different things.
You can take any average fat Halo2, Day of Defeat, Call of Duty, player, throw him into Iraq, and he'll get his butt kicked...yet, he's been playing the "best in simulation technology to date"...probably longer than most people have been training in the military.
Again, it's "on paper", even if it's digital.
The use of these simulations? To know what to expect.
Everything will need to unfold and be smoothed out in the field, but at least you can expect something, and watch for it.
Reminds me of Adm. Nimitz's comment on the war in the Pacific.
"We were prepared for everything, but the Kamikazes".
Never expected it, but had we had a simulation with a smart jack like the guy you mentioned, and thought to himself "well I'm out gunned, let me see what happens when I just fly planes into their ships"....maybe we'd have expected it, and been better prepared.