Enterprise is Great wrote:
The thing that's rather silly about the plan, though, is the need to fire all 72 torpedoes. Even if Kirk intended to use them, he could've decided using them all was too risky for starting a war, so he could've located Khan and fired only one or two at his position, which should've been enough.
Marcus really doesn't need all the torpedoes to be fired just enough to piss off the Klingons. He was expecting the Enterprise to be crippled (by his sabotage) and then attacked and destroyed by the Klingons thus destroying all the torps.
My thinking runs similarly - recall that Chekov discovered the malfunction and manually dumped them out of warp. I think Marcus plan was for that sabotage to cause Enterprise to get stuck much closer to Kronos where she'd be more easily discovered and destroyed by the Klingons - taking the evidence of the torpedoes with her.
With regard to the torpedoes themselves - I think the dialog stated that the fuel compartment had been altered to house the cryotubes. So I'm guessing they had live warheads (perhaps that is something that can be easily deteteced by scan) but if you tried to actually shoot them, they wouldn't go anywhere.