Aside from this specific case, I'd far rather hear somebody sing from memory and flub a word or two than read from a script.

Anybody can read from a book or a piece of paper, but only someone who knows a song inside and out can sing from memory. How many "source singers" regularly depended on written-out lyrics in performance? Or, worse yet, on some editor's written-out words?

The two kinds of performance convey a completely different feeling.

Joe, if you can sing 500 songs from memory, your song memory is a hell of a lot better than mine - and probably most people's.