I was thinking about Mark Plaajes - very friendly and nice, as long as he isn't doing physical therapy on you!
Mark gave me a black and blue "autograph" on my calves! ;-)
I was waiting to see Mark for PT one day, and in comes a Kenyan runner who was in Boulder for training. Mark asked him how he was doing and his reply made a lasting impression on me. "I am happy, my fiend, and that is all that matters".
I have met several professional runners, but the two that stand out to me as being extra nice are:
Mark Plaatjes for sure. I got physical therapy from him for a long while. He's the man.