Also “nah, yeah” can mean “I understand”. So if you want to say “I understand but disagree” it’s “nah, yeah; yeah, nah”
In Canada we use both, we’re very cultured.
The second bloke is completely missing the nuance of the “yeah, nah”. It doesn’t simply mean “no”. It means I’ve heard and acknowledged what you’ve said but disagree or have a different opinion. Examples
“Mate I’m fucked, want to go to kfc for brekkie?” “Yeah nah last time I went it was shit”
“Ah fuck my bad!” “Yeah nah it’s all good mate, no worries”
“Trump isn’t all that bad, I agree with his policies” “Yeah nah he’s a pedophile rapist, you’re fucked in the head mate”
Australians use “yah, no” and “no yah” the same way Wisconsinites do? That’s wonderful.
I’ve always used “Yeah, nah” as “I get what you’re saying but I disagree” and “Nah, yeah” as “No problem here with what you’ve just said and I agree with the sentiment”. I rarely use the latter though, at least as far as I know. It might pop out without me knowing.
Rural Mexico… Si, pos si si. Pero so no. No pos no. Si pos no! Pero si si si. An entire conversation.
Listen, all y’all, it’s a sabotage
As an Australian, whole we do say yeah nah a fair bit, the infamous nah yeah is slowly fading into obscurity, to the point where people are questing if it was ever used in the first place
Nah yeah y’all Nah yeah y’all Hey hey hey Nah yeah y’all



