Well I did it. My challenge was to learn 3 chords in 5 months and go and back up my friend at a Rock and Roll rally we were running. I did it., My stage name was ‘Tone Deaf’. The first 2 songs I had practiced a lot, but that afternoon he said to me “by the way, you will also be backing me up in Johnny B Goode. After all it only has the same three chords and you know the song like the back of your hand anyway”. We had a test run that afternoon (1 take) and then I played it in the evening. I never thought I would do that, but it was great fun.