Sometimes you just have to be politically incorrect and the current carriage-horse kerfluffle is as good a place to start as any. A Queens city councilman named Tony Avella wants to ban the carriage horses that work in and around Central Park, one of New York’s most charming and evocative tourist attractions, claiming they are abused and unhealthy. Today’s New York Sun begs to differ, citing a new study by a Cornell University veterinarian that says the horses are just fine, thanks. What I want to know is, why doesn’t Councilman Avella grandstand in his own neighborhood? Oh wait! He’s about to be tossed from office due to term limits — and he wants to run for mayor. Could that possibly explain it?