Super interesting story. My take (not having heard of her before today, and just reading the flotrack article):
- she was clearly talented and tough early on
- ran 2:44 marathon indoors in 2016, without marathon-specific training
- I'm not judging here, but in the pictures from the 2:44, she looks heavier than the average elite
So then add:
- a year-plus of consistent, marathon-specific mileage and workouts
- looks like some significant weight loss (but still looking really healthy and strong), which makes a *huge* difference over that distance
...and yeah, I believe a 15-min improvement. Terrific run and probably lots more potential to improve. Hope somebody signs her for major $$$.