He won't ever read this, but allow me to wish Sir Mick Jagger a very happy birthday anyway. I first saw him and the lads in a very seedy club on Eel Pie Island in the middle of the Thames, near Twickenham, in the early sixties. He probably still talks about it.
When it comes to longevity in entertainment, the Stones cracked it. Bill Wyman bailed out to go his own way, Ron Wood arrived decades ago (and seems to have always been there), and poor Brian Jones checked out early, though he'd already left the band before his death. But Charlie, Mick and Keith have gone all the way, and seem likely to keep rocking for years to come.
It's a great example of simply doing what you do well. Greg Norman showed similar qualities when he battled to third place in the Open golf championship recently. He succeeded in conditions that destroyed the games of younger players, because his long experience had taught him how to play in driving wind and rain.
Experience is what audiences pay for. A reassuring thought.