Stop It With the Fools Already （うんぽんたん）

He Says:
unpontan （うんぽんたん）=fool
Fool usually means aho or baka in Japanese,but unpontan too.This word unpontan is kind of soft word to say fool,we use it when we are not so angry with the people,or especially to kids,women who would be so hurt if we say aho or baka.
And this word is so old,they say it's made more than 300 years ago,which was Edo era in Japan.
Japanese use aho or baka many times in daily life,don't use unpontan even though it's the same meaning.
So they would think cool if you can use this old word instead of aho or baka!

She Says:
Good Lord, do we really need another word for fool? It amazes me how almost all insults in Japanese get translated as "fool", when it's just not so common in America. Stronger words in Japanese tend to sound ridiculous when you actually translate them (See hetare.).
Anyway, He says that because of the obscurity, you'll end up looking cool. I'm not so convinced of this. I mean, I think that many English speakers have at times encountered a foreigner who uses out-of-date slang. It doesn't make them cool. We're more likely to laugh AT them. Maybe Japanese people are different though...