Reviewing German sentences of other contributors, I found a bunch of sentences where the author circumvented the acronym detection by inserting dashes (BKA -> B-K-A). I don’t think this is how we should deal with abbreviations. The How-To should be adapted to be more explicit on this issue.
I must say though, that I don’t like the strict prohibition of acronyms. In many cases (such as BKA), there really is only one way to pronounce them. Maybe we should have a peer-reviewed whitelist of acronyms?