I agree with Pablo. These are all static calculations, and they don't account for thermal cycling, which can 'pump' moisture into the tank. Moisture contamination is a cumulative phenomenon.
The author mentioned diesel, but didn't exclude gasoline. He ignored the phenomenon of phase separation with E10. This has been discussed in detail in the recent past on this board.
"The weather can turn cold very fast, but does not suddenly get very warm."
Apparently he's never lived in Michigan, where the weather can quickly turn warm and balmy in the winter, causing everything in my garage to sweat like morning dew and rust.
His temperature conversion needs to be edited.