The whistling taboo may have a basis in fact, the reason it's frowned upon in the theatre is because whistles were used to signal the scenery shifting bods, who pulled ropes and made big stuff move, a careless whistle might be misinterpreted as an instruction to move something big, heavy, and downright dangerous...possably onto someone smaller and squashy. It might be that whistles were used in mines as signals too, hence the no whistling rule, which, over the years, as more modern communications came about, acquired an aire of superstitious mystery.....or it might be the Boggits.
Apparently on Royal Navy ships, it was used as a secret code signal during some mutiny that's why it's not the done thing for the skates.