Mike Vernon & the Mighty Combo

Question: What do Alexis Korner, John Mayall's Bluesbreakers, Eric Clapton, Steve Winwood, Spencer Davis, Jack Bruce, Rod Stewart, Ginger Baker, The Artwoods, Muddy Waters, Savoy Brown, Otis Spann, Johnny « Guitar » Watson, Larry Williams, Graham Bond, Ten Years After, Stan Webb, Peter Green Fleetwood Mac, Champion Jack Dupree, Christine McVie, Mick Taylor, Eddie Boyd, Dr. Feelgood, Freddie King, Climax Blues Band, Roger Chapman, Cleo Laine, Jimmy Witherspoon, Level 42, Roachford, Sherman Robertson, The Hoax, Oli Brown, Keith Richards, Ron Wood and Bo Diddley all have in common?
Answer All have, at one time or another, been involved in the making of records that have been produced by Mike Vernon.