An authority changing its rules or rulings does not in any way diminish its authority or invalidate it - or we would have given up on courts long long ago.You're in a thread about the Shield Mastery feat where the guy you are quoting as the definitive authority on RAW changed his mind 3 years later to do a complete 180 turn on what is RAW. You see the irony of you claiming he's the definitive authority on RAW in this very thread, right?