What about the effect of instrumentation on the abillity to learn the words?
I find that I larn and remember the words better of songs that I hear unaccompanied.
Conversely the radio station that I listen to on the way to work has a daily competition where pop song lyrics are read out. I never reconise them even if I know the song well because it's the tune that I listen to, not the words.
Is it something to do with me hearing tunes as a series of chords with a melody over?