To me, "cheers" (by itself) seems too light/insincere or even sarcastic (almost like saying nothing at all), but "thank you" (by itself) sounds very stilted/forced.... yet together it comes naturally.
Is this normal/attested? I've never heard other people use it as much as I seem to do. Can an XP be reduplicated systematically like this in English?-- e.g. "Go on; get the hell out of here!" seems to have more illocutionary force than either "go on" or "get the hell out of here" by themselves, unlike the "double politeness" listed above.