YARN
Fleet Captain
Why would it do that latter bit? It's not actually chasing the Enterprise: it's trying to shake her off so that it can go to Rigel.
It's not really trying to do anything. It's a mindless machine following its programming. It's attracted to the power that emanates from warp nacelles and will attack a starship. The machine "loses interest" if a ship gets outside of its defensive perimeter, but it will focus attention on a ship that travels within that sphere. When the Enterprise closes within its attack range, the programmed thing for it to do is to turn and attack. It's not like its watch and muttering "Dammit, I really need to get to Rigel!"
The Doomsday machine heads off to Rigel moving from left to right. The Enterprise pursues, also moving from left to right. We get an intervening scene on the Constellation where Kirk is apparently spot welding. Next, we return to the Enterprise. She is still moving from left to right. We cut to the Constellation and she is moving in the opposite direction, from right to left. In plain English and following the grammar of television the message is indubitable - the Doomsday Machine has turned around.
If it were capable of warp insystem/immediately/whatever, it would leave the starship in its wake. Since it doesn't, there's something strange going on if it is warp-capable - but nothing amiss if it isn't.
As you said, it might have to move outside the system to engage its warp drive.
Then again, the Enterprise is warp-capable at this point too. If the Enterprise really is faster at warp, then it's plausible that she could catch up to the DM after giving it only a 4 minute head start (this is much different from the 10-15 light year head start involved in doubling back, and picking up, and clearing the interference, and notifying Starfleet, and then allegedly scooting off to cut it off before it reaches Rigel).
Excellent point. Then again, TOS-R shows us that "visibility" is limited by dense rubble,
When the two come into conflict, the original show (being the original), should take precedence in out interpretations. Or, if we insist on being democratic, we should take it that contradictory evidence from two equally legitimate sources requires that we must pass over such evidence (i.e., it cannot be counted for or against any given interpretation).
and even the original dialogue establishes our heroes are isolated by subspace interference.
When they scan L-370 they are able to discern with their sensors that that solar system had been destroyed.
Later, when they enter the limits of L-374, they are able to detect that the inner two planets (and ascertain their composition) are intact while everything else is blasted to rubble.
During these scenes Kirk orders sensor scans, and his officers comply. No one complains that their sensors are "wonky".
Their radio communications are suffering interference, but at no point are we told that there is anything amiss with the sensors. Palmer (the communications officer) complains of interference, but not Spock or Sulu. Ergo, we have no reason to believe that navigation or the science survey aspects of the ship are suffering these effects.
That they "can't take much more of this" before anything actually happens could be due to one of two things:
1) The DDM drains the ship's power by its third weapon, the one that isn't the tractor beam or the antiproton beam - the one that deactivated the antimatter aboard the Constellation. This could also explain the seven-hour fuel limit thing.
2) Spock is simply saying the deflectors can't do a repeat performance of the first encounter, as a preemptive warning to Decker.
Or we accept the most plausible explanation. They are being fired upon. We are getting caught up with a battle in progress. Check out how the scene plays at CBS.com.
A straight-line course of the battle away from the Constellation at best DDM speed would also match the facts, as long as best DDM speed is lower than best Constellation speed. The fight could merely keep the DDM from doing what it wants, namely accelerate to interstellar drive mode.
I don't think so. If the battle was not heading toward the Constellation, but away from it, there is too much ground to cover (again, this is simply bad writing offering us the convenience of putting Kirk right there to get into the fray).
Scotty and Decker argue for 4 minutes while the DDM runs for it. We then get the fanfare with a fly by shot with the Enterprise shown gaining on the DDM. Cut back to the Constellation where Kirk and Scottie spend a few minutes chatting and repairing. Basically, if we interpret things your way, the Enterprise (which can do much better than 1/3 impulse - she's still warp-capable at this point) should be at quite a distance from the Constellation.
Before the Constellation even engages her engines, however, when Kirk first looks through the view screen it looks as if the battle is right outside the ship.