Rolf was a Saturday night staple for my generation with his amazing quick paint style with a story or song. Do a Rolf search on You Tube and you will find practically all of his TV work. I would even compare him with Ranulph Fiennes for drive!
I can still recall his swimming information films in the early 70's and who can forget "Two Little Boys"? Every Friday afternoon at work , my manager fills in a white board using a marker pen showing next week's work and the number of people who walk past him and say "can you tell what it is yet?" never drops!