ThreadMode is great, but any kind of dialog can easily get off the path of healthy discourse and onto the path of YabbitsAndAntiYabbits:
Up is up, and down is down, there's no arguing with that.
Yabbit, there's always sideways, and we have to consider that.
Yabbit, what I'm saying is that in turns of verticality, there is up and there is also down.
Yabbit, you're wrong in saying that, because of the whole left-to-rightness issue and how it intercedes.
...and so on, ad infinitum...
If you find yourself saying 'Yeah, but...' too often in a dialog, whether you use those simple words or not, give it a re-think. On the other hand, if someone's yabbiting you, it's a good time to OnlySayThingsThatCanBeHeard.