As to the neutral zone being three hours from earth - I don't think I can buy that. The neutral zone is always represented as a border posting for starships, like they're being stationed out on the frontier, far away. Just because they were using primitive warp drive doesn't mean that the war was fought so close to earth. Besides, I always thought the neutral zone was a negotiated treaty that simply drew a line in space that said, here and no further. Who said it necessarily was drawn right at the boundary of romulan or earth space? The earth forces could have been pushing the Romulans back further and further until they sued for peace, thus the neutral zone would be farther form earth.
Added to that, whenever they were stationed at the neutral zone, Kirk never had direct access to SF command, subspace radio, which traveled MANY times faster than the ships (I think I saw a figure that said something like Warp 20 on the old scale.) took many hours if not days to reach command and get an answer. So when you were stationed at the zone, you were esentially on your own. That seems to me to indicate a neutral zone that is FAR from earth, not hours away but days away at warp.
BTW the lastest info on the Federation states that it would take a staship months to cross the Federation from one end to the other yet every where where a starship has to go it only takes days or hours on the show and in the movies....
