John,
I suppose you don't have to be old enough to have watched the Cardinals play at Sportsman's Park on Grand Avenue, but being that old certainly increases one's chances of having met Keith and/or O'Connor.
It should come as no surprise that O'Connor was the more polished writer. After all, he was an English teacher!
There are also many who don't have a clue about how much Elmer actually wrote in the way of private communications and that he did it all on a manual typewriter with no "white-out". Typos were common, especially without time to go back and do the corrections needed before moving on to the next response.
The thing that strikes me as being extraordinary was Elmer's accessibility. He really didn't seem to have any reservations about people calling or writing and usually had time to devote to them. The comments I've heard have been along the lines of it being like talking to a grandfather/mentor, not a celebrity.