There are sites on the Interweb that state Dennis was born on 26/9/47. Now, where they got this info from, I don't know, but I assume that at some point (before it became a state secret) it was possible to find out such information and that it was recorded and has been passed down. This leads me to thinking that the gig at the ICA could be a kind of 60th birthday celebration. (Or, if other detectives are right, a 55th birthday celebration.) I tend towards the 1947 hypothesis because if he was born in 1952, why would he be so secretive about it? A