Astonishing stuff

Michael Schumacher, in "Crossroads: The Life and Music of Eric Clapton," writes that during the musician's year with the Bluesbreakers, Clapton "had developed his creative and technical abilities on guitar at an astonishing rate."
After listening to John Mayall's "Blues Breakers with Eric Clapton" for the past several days, I can't help but agree with Schumacher's assessment.
Clapton's guitar playing is amazing on this album -- which Schumacher calls "one of the great British blues albums of the period" but what I think must surely be the greatest British blues album of ANY period.
Mayall is great as well, whether he is blowing his harmonica, banging on the piano or organ or simply singing with a distinctive voice that wholly suits the blues.