I don't think it's possible to sap the gunslinger...that'd be an interesting glitch though...explosion kills Engineer...hmm...
Logically speaking, if Spy wanted to be a dick he wouldn't bother with the machines but actually focus on the Gunslinger itself.
Actually, scratch that. Logically speaking, if Spy REALLY wanted to be a dick he wouldn't need to uncloak just to backstab somebody...
