I can't recall the details, but I seem to recall one of what must have been either the last or second last season, when Kevin was dating an immigrant girl, and she said something like "she liked American music-especially the Beatles." Was this supposed to indicate that she was stupid or was it an error in the writing?

That girl was Inga, the exchange student from Sweden in the episode "Double Double Date" from the 1991-92 season. I couldn't understand why she called the Beatles American (except possibly because they were popular here) when they came from England originally.

I can't recall the details, but I seem to recall one of what must have been either the last or second last season, when Kevin was dating an immigrant girl, and she said something like "she liked American music-especially the Beatles." Was this supposed to indicate that she was stupid or was it an error in the writing?

No way the writers could have made an error that big. I'm sure it was just a line that was meant to show that Inga was ignorant.

I don't remember that specific episode or that line (about American music), but someone listening to the Beatles without knowing their history could conceivably have mistaken them for an American group, since their British accents did not come through in their songs. When they sang, they "sounded" American... when they just talked,that's when their British accents came through.

Singing tends to mute accents.

Rolling Stones, same thing... when they sang, you can't really tell they're British... but when they just talked, it was obvious. That was true of all of the British Invasion groups.

Whether or not someone growing up during that time (that TWY took place) could be ignorant of the Beatles origin is another story. But you can't tell they're British by listening to their albums.

Yeah i think that song was in the 5th season of TWY