I agree on the singing during the high energy songs but not so much on the ballads.

However... my take also has to do with how the ballads are sung. Take BOY for instance. If it's performed like the album version, like how she did it at MSG, that's fine. But if it's performed like the MTV/VH1 performance, then we should be quiet. Songs like Beautiful Disaster and Why shouldn't be sung along to IMO (even though we all were singing along in LA on the first verse).