Hey LMP,
I have to say I based my comment on pure my own experience. I saw FS racing several times. Sadly only saw Mike once in '67 as a little boy and in '80 when he did 2 exhibition laps in Assen on the 250/6. Saw Sir John twice, once during the Centennial in Assen and on Spa. You could see the talent even on his high age. In my defence think that the opposition FS was up against might be slighty bigger. but all of them, by the way even the back markers from the day, deserve our deepest respect.
Rob