Scott, the lone exception is Dave Boyd..He has the best recollection of lyrics and can tackle any song on the fly, using adequate chords and a proper bass line..

I can remember songs I have played for 40 years, but can never understand how someone can remember all the lyrics..
I have worked with young ladies that needed a key first word to remember tunes..

No need to defend yourself using a music prompt...we all have used them over the years...the key is not to use them as a crutch..