Acting and being

Modern stage actors are under criticism for mumbling too much, with the effect that audiences can't hear them properly. The culprit, apparently, is a passion for naturalism, a desire to seem real as opposed (I guess) to 'stagey'. Not that I know anything about it, but someone involved in the training of young actors must surely have pointed out that acting is, when all is said and done, acting and not reality, and that if it can't be heard, then all the fine realism of it is to no avail. Actors compromise in so many other ways: like by affecting to be miserable when they're not, or happy when they're dejected; and by not really dying when they're 'killed'. A bit of sound, therefore, doesn't seem like a lot to ask.