I string with D'Addario phosphor-bronze on my 6, 12, and baritone guitars, and mandolin. All are solid wood tops backs and sides. I used to have a couple of solid top/laminate back and sides guitars which seemed to sound better with bronze strings.

I figure the problem with Mr. Fingers' situation has to do with body oils or sweat, atmospheric conditions, airborn dust, or maybe even a changing ear or preference. I've a friend who can kill a set of strings in an afternoon of playing but it will take me a week of hard jamming...his hands are greasy even after a wash. I restring often cause I make my living at this, but I can hear a difference within a couple of hours of play but find the sound quite acceptable for days, less acceptable for another few days, and un-intonate-able (unintonable?) thereafter. This on my everyday teaching and first call performing flat-top.

Flesh does sound different than picks so maybe some fingernail is in order?

Peace, Mooh.