The problem they would have then is that most people would feel that there is no "worship" going on at the K.H .
Lets face it, there is prescious little at present that resembles worship.
Also the mind -control experts at HQ know that much of the dogma (dogsh**) is re-inforced by even mumbling the lyrics,plus endorphins are released in the brain for those that "sing out" so they feel that they, the singers, have had a real spiritual experience,instead of the sham it is.
No way will they let go of this ,it would add to those leaving. That god-awful singing is here to stay at the Kingdumb Hell. I'm glad I no longer have to endure it.