You should've worked faster and now you must pray you wipe out the remaining terrorists. They don't autogive you a defuse kit just because you didn't get to the ticking bomb in time to defuse it without one.
I think the intentionally killing of hostages by either side in an attempt at an easier win is just plain low.
If hosties were as dumb as they are, I'd agree. But often times your strategy would have worked perfectly if it wasn't for the hosties' death wish.
I think what matters though is whether or not this is a CAL rule or not. If it is than keep it, if not I officially call it into question.
I do bend on dee-dee-dee hostages, where three out of the four are going fine but that fourth found something interesting on the wall to stare at. Sometimes you gotta shoot that one. I don't agree with only grabbing one hostie and killing the other 3 right off out of mere convenience though.
I say give the rule as it is written a shot.