I think a proper producer should make a band sound like themselves....but better.
Spector had a good idea....the "Wall of Sound". 7 parts good composers, 1 part malleable, attractive young female singers, 2 parts quality production. But to me it's all pretty much much of a muchness. High quality stuff, like Henry Ford's Model T. Wah bloody hoo, who wouldn't love a proto-X-Factor?
Dee Dee, Marky and Johnny didn't play a single note on "End of the Century". Rock and Roll, you gun toting,murderous wiggo!