All these arguments about Bono's vocals started way before "Pop" or ATYCLB (or now - even though most admit Bono sounds much better now). They actually started with AB and ZOO TV. I often used "Night and Day" as an example that what Bono did on AB was intentional. "Night and Day" was recorded in 1990, the same time U2 were starting work on AB. So Bono wouldn't go from that wonderful performance to "a ruined voice" - especially given that U2 were pretty quiet most of 1990 and '91 (until "The Fly" was released) and that Bono suffered no serious illnesses. In other words, even today, while some of Bono's scratchiness is due to age (and smoking and drinking) some is also intentional. For example, "One" would not be the powerful song it is if Bono sang it in his "pseudo-opera" Love Town voice.