Gaining strength from the applause, she steps forward at an ever increasing pace, until she is right on the apron of the stage, eyeballing those in the front row. At this moment, the Dame stamps her foot and throws her hands into the air. Out of sheer terror, the front row stands up. The second row stands up because the first row has obscured the view. And so on, job done.
Television is a closeup and sometimes more subtle medium.
I have watched Bert Newton appear from behind a curtain to receive applause from a studio audience. He stands there beaming with his hands clasped in a Bertly manner and the applause continues. At the exact moment when there is the slightest suggestion that the applause might finish, Bert, with the slightest effort, shifts his weight almost imperceptibly on to the other foot. Unconsciously taking his cue that the time for applauding is not yet over, the audience continues to clap and cheer until Bert is ready to release them. The difference between the Dame and Bert is that Bert is so at one with his medium that he probably doesn't even realise he is doing it.