Come to think of it, that suggests another interpretation. Scotty didn't say their propulsion was simple impulse, he said their power was. Maybe he meant that their weapons were powered only by their impulse reactors rather than their warp reactors.
Naah, that doesn't work, because Kirk's next comment is "Meaning we can outrun them?", which Scotty agrees with. Clearly, "power is simple impulse" has something to do
directly with outrunning the Romulans, not outgunning them.
(Although that clashes a bit with TMP, where channeling phaser power through the warp drive was presented as a novelty.)
Might be a thing that comes and goes in future naval history, much like, say, turret-mounted guns did in our naval history.
I figured he meant that (at the time asked) the BOP was travelling at impulse, because they were under cloak.
But Scotty wouldn't have seen their powerplant when they were under cloak... So more probably his guesswork was based on what he glimpsed when the Romulan ship briefly emerged for firing at the outpost.
And that could be misleading him in many ways. Perhaps the Romulans have to shut down their warp power when firing the big plasma gun? Perhaps they have to reroute warp power to that thing, meaning Scotty doesn't correctly identify the power signature? We know the ship was more or less the match for Kirk's ship in speed during the long flight home, regardless of whether she was cloaked or not. So perhaps the traditional fan opinion is wrong: perhaps the cloak isn't the power-hungry thing aboard that ship, but the plasma gun is?
Whatever the exact nature of the Romulan power system, I think it is defensible dramatically and continuity-wise to say that Scotty was mistaken here. His "simple impulse" would give an imperfect view of the reality at best, and might turn out to be completely false at worst. It works both within the context of the episode (the enemy is unknown and full of surprises), and the greater context of the series (the heroes are fallible, but don't fault each other for failures, and take new developments and suddenly disproven beliefs on the stride).
Timo Saloniemi
