John Surtees was a very great driver, and rider. As a person and at least to a hack asking questions he thought obvious or trite, he could be difficult. Curmudgeonly even; at times dismissive to the point where a more sensitive soul might consider him rude. I learned this the hard way when, at a Goodwood lunch I was sat next to him and asked him whom he considered to be the greatest driver of all time.
There was a long pause, I expect because he was considering whether such a stupid question even merited a reply, after which he explained somewhat tersely that there was no such person. How could you compare drivers from different eras facing different challenges in different environments using utterly different equipment?