I often find that “Hm. So you’re saying XYZ? That doesn’t really work, because of ABC. But now that I think about it, X’Y’Z′ would be consistent with what you’re claiming, and not have that problem. Even there, though, A’B’C′ suggests it’s false.” can work all right, although I’m often tempted to add “But of course by this point I’ve wandered off into a corner and started arguing with myself, which seems antisocial.”
I think that in some contexts, like arguing over mathematical proofs (as orthonormal noted), spending a little time arguing with yourself to bring out X’Y’Z′ is polite and a sign of good faith. In other cases, I’d rather just trot out A’B’C′ early on, as long as it doesn’t require too much effort, and deal with both arguments at once without ever explicitly raising X’Y’Z′.
Depends on how it’s done, IME.
I often find that “Hm. So you’re saying XYZ? That doesn’t really work, because of ABC. But now that I think about it, X’Y’Z′ would be consistent with what you’re claiming, and not have that problem. Even there, though, A’B’C′ suggests it’s false.” can work all right, although I’m often tempted to add “But of course by this point I’ve wandered off into a corner and started arguing with myself, which seems antisocial.”
I think that in some contexts, like arguing over mathematical proofs (as orthonormal noted), spending a little time arguing with yourself to bring out X’Y’Z′ is polite and a sign of good faith. In other cases, I’d rather just trot out A’B’C′ early on, as long as it doesn’t require too much effort, and deal with both arguments at once without ever explicitly raising X’Y’Z′.