Ahh. Okay now I get it. I was thinking that the neutral zone was a straight "line" wall, not a sphere zone that surrounds the Romulan Empire.
So several questions spring to mind:
1. At the smaller scale, couldn't the Romulans fire at these Starfleet outposts from their own planet? The Plasma weapon had a very long range.
2. or build a set of counter outposts on their side and wouldn't they show up on the map?
3. Where is Remus?
4. If the Romulans have been circled in for a hundred years, shouldn't Starfleet Intelligence have some good visuals on any Romulan ship design prior to the introduction of the cloaking device?
5. Wouldn't the "stars of home" look the same on the other side of the neutral zone to the Romulan Commander if the fight took place in their own star system?
6. Couldn't Starfleet then start shooting at the Romulan homeworld from their outposts as a response since they're at a close enough range.