This word is different from the ones I talked about before: I had never heard it used until someone mentioned it on another blog. My first reaction was: This must be a neologism that occurred after I left Germany. But then, thanks to the wonders of the web, I found a source that is over 200 years old: Someone complaining--at the beginning of the 19th century--about the editors of the play by Kleist, Der Prinz von Homburg, who, in the attempt to improve upon Kleist’s language, actually made it worse. And that’s exactly what the term means: An intended improvement that has the opposite effect (the adjective schlimm can mean anything from "bad" to "malicious"; the noun Besserung means "improvement"--literally "betterment")--a useful word indeed, given how often we have seen so-called "reforms" that make a situation worse.
Details in my first comment.
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