Well, well. Actually going back and watching the movie as a whole, rather than as a series of snippets, was both fun and informative...
- The original question of why 72 torpedoes would be needed is a misguided one. The movie never features the concept of firing 72 torpedoes.
Rather, Kirk's ship is stocked with torpedoes, either as many as she can carry, or then as many as there exist. We see plenty of room for more torpedoes in the shuttlebay, so the logical answer is the latter. And Khan, as part of his plan, could easily have seen to it that only 72 torpedoes (the special ones) would survive his bomb strike.
But having those 72 torps aboard is Khan's plan, not Marcus'. Marcus would be within his dramatic rights to simply order the loading of all existing long range torpedoes on the Enterprise, in hopes that Kirk expends as many of them as he can before being martyred. That is, the Admiral might plausibly miss the fact that the number is a familiar one.
Sulu never says he is going to fire all the torpedoes; indeed, at that point, some still reside on the shuttlebay deck. It's just that, after triumphing in the planetside fight, Khan suddenly asks Kirk a complete non sequitur, and Kirk sees no reason not to answer (as this might save his life for the moment). Khan wants to know how many torpedoes there are, not how many should be fired at him.
So we don't need to try and rationalize why Marcus wanted that many torps fired. That isn't part of the movie; Marcus just provided Kirk with ammo and told him to finish off Harrison with it, and Kirk would no doubt have used his tactical judgement in the actual firing.
Which probably means he was given some sort of specs on what the torpedoes could do, as a basis for such judgement. Possibly false specs, even, so that he would think in terms of a surgical strike but would end up massacring a planetful of cute Klingon babies.
- Khan says he was exposed, but he never says his plan was. So odds are that the plan proceeded as, well, planned (at least in its v 1.1 form, the one that included saving that girl's live, bombing the archives/arsenal, and shooting at the admirals): the crewsickles in the torpedoes got delivered the way Khan intended, even if he temporarily may have lost hope.
- There's quite a bit of screen time, never mind in-story time, for Spock to take the cryotubes out of the torpedoes. The last time we see sickbay free of cryotubes is fifteen screen minutes before the torps are beamed over to Khan, and that must be at least half an hour of in-universe time - but the existence of the cryotubes is revealed much earlier and gives Spock hours to perform the act behind Khan's (and, necessarily, Kirk's) back.
- Nothing suggests the Vengeance would have been unique or even supersecret, or that the dreadnought category of ships would have been. All we learn is that the specific dockyard wasn't open to public and that Kirk wasn't among the Starfleet personnel informed of the project.
- Khan's rambling about the aft nacelle isn't a fumbled line - it's a (fumbled?) looped line, spoken while the camera is pointed elsewhere. It almost looks as if the line originally was shorter and didn't have the "located" bit, but was artificially extended in the editing phase to allow for a reaction shot that was deemed important.
- While Kirk's ship gets some momentum from Khan's phaser blasts just before the torpedo detonations, we don't get the things I was hoping for: absence of the Moon from the shots when the firing commences, or plausible slots for extra time in the sequence. So the aphysical plunge from the Moon to Earth still is about a day or three too fast.
- OTOH, that detonation scene shows pitifully small explosions in terms of what would be needed to really bring down Harrison at Ketha... Unless we assume the Vengeance hull contained the explosions superbly (but they don't get appreciably bigger even after the hull is ripped open).
Make of all that what you will. But we really don't have to worry about the plan being to fire exactly 72 torps at Harrison, because that's never specified.
Timo Saloniemi
