Can you hear the people sing in Les Miz? Then thank these sound pros

I saw Les Miserables on the big screen again yesterday (the Grove in L.A.) and I'm still besotted. I went with Russell, my filmmaker son who has not been a huge Hooper fan - he thought Social Network was a superior film and should have won Best Pic over The King's Speech.  I wondered whether he would love it or reject it and was happy that he shared the Les Miz movie love that MLH and I share. When we came home he started watching all the craft featurettes I've been sharing here and then he found a fascinating one on sound design that I missed so I'm posting it here.