In Mozart's time is was the done thing to clap and cheer even in the middle of movements. By the 1970s in classical concerts you were considered a buffoon to be silently snarled at if you so much as indulged in polite applause between movements. "Huh, didn't he realise that this is a SYMPHONY, not four separate tunes!" Good to hear a lot more cheering and clapping coming back. Let's unstuffify music!