I never said it wouldn't. I agreed up front that this would detect a bomb without interacting with it 50% of the time. It's a minimally-functional bomb-tester, and the way you would optimize it is by layering the original bomb-testing apparatus over this apparatus. The two effects are pretty much completely orthogonal.

ETA: Did you just downvote my half of this whole comment chain? Am I actually wrong? If not, it appears that you're frustrated that I'm reaching the right answer much more easily than you, which just seems petty.

Also, these are not nit-picks. You were setting the problem up entirely wrong.