Absolutely. The point is, that the NZ must not be a clear, straight demarcation, because otherwise there's no logical way the Enterprise would need to go through it. It must be misshapen and protrude to an extent into Federation space, so that going around the rim would take longer from the Enterprise's side of the protrusion to the Starbase's side. Thus, to save time Decker cuts through the NZ. That's my interpretation, anyway.
What do you mean by "misshapen"? Are you claiming that a border that isn't perfectly flat is ugly and misshapen?
Suppose that interstellar law in Star Trek allows a government to claim all the space within a distance of one light year around a star, for example. Then the border of that space state would be a spherical shell with a radius of one light year around their star. And if that government rules several stars, it would have 1 light year radius spheres around each of those stars. And since the average distance between a star and its nearest neighbor in our part of the galaxy is about 5 light years as far as I know, ships would have to cross open space free to all travelers to travel from one star system to another in that space realm.
So in that case the map of that space realm would show a number of disconnected spheres surrounding stars, and floating in three dimensional space.
Or maybe the space realm would be allowed to claim cylindrical volumes of space connecting the spheres of space it rules.Those cylinders might be one percent of a light year in diameter, for example, and extend at least a few light years if connecting two very close stars, and farther if connecting more distant stars.
Thus the map of the space realm might show it looking like a three dimensional model of a complex molecule.
If a space realm is allowed to claim a sphere of space around each of its stars that has a radius that is greater than the average distance between two neighboring stars, then the spheres around the stars that it rules will overlap, and the map of that space realm will look like a three dimensional sculptured consisting of partially overlapping spheres.
And in that case if the space realm expands in every direction and gets to be much larger than the average distance between stars within it, its shape may resemble a sphere, with some degree of lumpiness resulting from the smaller spheres around the outermost layer of stars.
And if two such expanding space realms meet, the border between them should become a flat disc which should expand in diameter as both realms expend in radius.
I guess that is the type of border that you imagine would be normal between space realms.
There are many discrepancies about the speeds of starships in various episodes.
One theory to explain those discrepancies is that sometimes a starship will travel between Sar A and Star B by travelling straight through all of the space between them, and sometimes not. Sometimes a starship will get from Star C to Star H by travelling through a series of space warps; disappearing from Star System C and instantly reappearing in Star System D, and then disappearing from Star System D and instantly reappearing in star System E, and then disappearing from Star System E and instantly reappearing in Star system F, and then disappearing from Star System F and instantly reappearing in Star system G, and then disappearing from Star System G and instantly reappearing in Star System H. Thus the only travelling a starship would have to do in such a s voyage would be travelling from the exit of one space warp in a star system to the entrance of another space warp in that system.
And possibly the systems connected by such a space warp might be varying distances apart, so that a tarsip might jump 142 light years in one jump, 48 light years a second jump, 13 light years in a third jump, 714 light years in a fourth jump, and so on, to reach its destination.
And if that was the case the , the Federation might contain many separate volumes of space that it ruled, connected by space warps leading from a star in one section to another section. And the same would be true for the Klingon Empire and the Romulan Empire., etc.
In "Whom Gods Destroy";
SPOCK: Fascinating. What maneuver did we use to defeat the Romulan vessel near Tau Ceti?
KIRK 1: Very good, Spock. The Cochrane deceleration.
KIRK 2: Spock, you know the Cochrane deceleration's a classic battle maneuver. Every Starship Captain knows that.
Thus a section of the Romulan Neutral Zone might be somewhere near Tau Ceti.
In "The Deadly Years" a section of the Romulan Neutral Zone and the Romulan Empire is directly between Gamma Hydra (which should be Gamma Hydrae) and Starbase 10.
And we all know that that Gamma Hydrae is several times as far from Earth as Tau Ceti.
"Balance of terror", set near the edge of the Romulan Neutral Zone, begins when a wedding in the Enterprise chapel is interrupted by trouble. And at the end:
KIRK: How many men did we lose, Bones?
MCCOY: Only one. Tomlinson. The boy who was getting married this morning. His fiancée is at the chapel.
(Kirk turns to go, and Rand enters)
RAND: We finally received an answer from Command base, sir. They say they'll support whatever decision you have to make.
So it takes less than 12 hours for a one way subspace message between this part of the Romulan Neutral Zone and the nearest command base.
The Enterprise crosses the Neutral Zone and is trapped by Romulan Ships in "The Enterprise Incident":
KIRK: You understand that Starfleet Command has been advised of the situation?
TAL [on viewscreen]: The subspace message will take three weeks to reach Starfleet. The decision is yours, Captain. One hour.
If it takes approximately 3 to 12 hours for a message from the Romulan neutral Zone to reach the nearest command base in "Balance of Terror", and approximately 17 to 25 days, or 406 to 600 hours in "The Enterprise Incident", the section of the Romulan Neutral Zone in "The Enterprise Incident" should be about 34 to 200 times farther away than the section of the Romulan Neutral Zone in "Balance of Terror".
In a few episodes episodes Kirk has conversations with Starfleet commodores and admirals who should be at the very least several light years away. And there is no lag in the conversations like the three second lag in conversations with astronauts on the Moon. So "Balance of Terror" would be at least 3,600 to 14,400 times as far from Starfleet as the Enterprise was in those episodes, and "The Enterprise Incident" would be at least 487,200 to 720,000 times as far from Starfleet as the Enterprise was in those episodes.
Do you really want the border between the Federation and the Romulan Empire to be a flat plane extending for all those hundreds and thousands of light years? If that was the case, there should be countless millions of star systems on the Federation side of the neutral Zone,and countless millions of star systems on the Romulan side of the neutral Zone. One would expect that each power ruled countless thousands or millions of inhabited planets, and they should have countless thousands and millions of space battleships in their fleets.
So it seems to me much more probable that space reals ms like the Federation and the Romulan Empire contain many separate volumes of space scattered through three dimensional space and connected only by space warps leading between them. One section of the Federation might be 10 light years from another, and lead to a third section which is 100 light years away, leading to a fourth section which is 26 light years away, leading to a fifth section which is 618 light years away, and so on.
And thus the Romulan Neutral Zone should have many curved surfaces, proably all of them spherical zones around various stars, and there should not be any flat planes in the geometry of the Romulan Neutral Zone.