I don't know if there could be an "all-time Greatest" songwriter...It depends on taste...Lennon and McCartney have to rank because of success, but I'm not a big Beatles fan...Zappa was a bit strange but his guitar"isms" and songs had many moments of genius. (When asked once, Vai said "Frank Zappa invented the Steve Vai"!) There are too many great blues songwriters to mention if that's what you dig. (Muddy Waters, Willie Dixon, Robert Johnson should be considered because of the influence that is still notable.)
Clapton has been a successful and very eclectic songwriter covering many different musical eras and styles..

Blues and Jazz are my fav kinds of music and that's how I make my living, but I grew up in the 80's so most of my early influences are the Hard Rock and Metal guitarists from that era..I'm a bit partial to those dudes...John Sykes is probably my favorite guitarist/songwriter (since he's the reason Whitesnake enjoyed their worldwide fame!)

VooDew5
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