Uncommon;
Sir, until you KNOW what you are talking about and do some research, please stop your rude insinuations. The rule came about in the US due to LAWYERS and civil litigation. We are only supposed to use the word Heavy when giving traffic and don't use it for normal transmissions in the US enroute system. Now the pilots seem to like to use it, it shows status and pay level <BG>...
regards
Scott