[Stiglr]

The Heirarchy tool tip certainly worked; didn't know about that one! Thanks, it solved that problem, at least.

As for the original problem, I figured it out. I simplified things by taking just a fuselage section into a completely new file, so I could be sure how many objects there were or weren't.

The problem is, the original B operand, the fuselage, remains, intact, after the cut is made in this scenario. This should be changed though: if you're cutting A out of B, an uncut version of B should not be hanging around after the operation, in the exact same physical position, and having the same material color: what becomes CSG0 is what should be left, no matter whether it retains the original name of the object or not. Do you see how this can seemingly result in "nothing happened"? That's exactly how it "appears". It's confusing.

Anyway: the solution is to check BOTH operands for deletion, and the result is GSG0 after the operation, the properly cut piece. You can rename that fuselage and continue happily with your work. But selecting this arrangement in the Boolean dialog, to me, seems like I'm saying, "cut part A out of part B, and then delete both objects, leaving absolutely nothing", when what I want to do is "cut part A out of part B, leaving a part B with a hole in it".

Another day, two more lessons learned.