Not a FM Mike Klein fan, but it is Running Related.
The idea of "disciplines" is a rather novel invention by chess boffins, as the same players largely dominate all of them. Even in the more esoteric. Blindfold was played for awhile (Melody Amber) but still the top guys are mostly the same, as also with Chess960 (Fischer Random Chess). I don't think Basque Chess (two games at once) has ever taken off enough to see the top echelon play it much.
Perhaps Pre was more long-distance than middle in his analogy, though St. Louis Rapid is 25 minutes (compared to 15m in other places).
https://www.chess.com/news/view/nakamura-mamedyarov-lead-as-st-louis-turns-to-blitz