I think Pino has to take the crown. These are the associated acts from his wikipedia page, which barely mentions the lesser known US R & B and neo soul acts he's worked with in the last 10 years.
The Who, John Mayer Trio, The RH Factor, The Law, Spinal Tap, Jools Holland, Paul Young, Genesis, Eric Clapton, Jeff Beck, David Gilmour, Richard Ashcroft, D'Angelo, Joe Walsh, Don Henley, Roger Daltrey, Hank Marvin, Simon & Garfunkel, Erykah Badu, Adele, Nine Inch Nails, Joan Armatrading, Geraint Jarman, Mango, Gary Numan