He certainly was, played the lute and guitar with a folk group based in Hove called the Brighthelmstones. We lost touch when I was moved away with work in 1977 (I was with Beecham Pharm, initially at the Worthing site at Clarendon Road).
This sounds a familiar name, Jon also had an "XX" entourage. I remember numerous after work sessions in the Railway Hotel opposite the station: I think it's been renamed now.
I think the Lorelei was in Union Street. We used to frequent the Cottage because you could get something to eat at one or two in the morning, which wasn't easy in the Brighton of the early 70's.
I also remember the 66 Club and Jimmy's, surprised no-one has posted anything about the Big Apple Club that was located in the ballroom above the old Regent Cinema at the Clock Tower. The entrance was in Windsor Street.
http://www.mybrightonandhove.org.uk/page_id__9767.aspx.
Reading the above...