I'd be interested in seeing a follow-up study on how this affects things like BMI, muscle gain/loss, vitamin/mineral retention, etc. From what I learned in bio/nutrition, I would assume that the body isn't able to effectively make use of the food consumed in this limited window. Some problems I see with this are:

Gluconeogenesis converts proteins to glucose to fat resulting, in reduced effective amino acid intake.

The digestive tract doesn't have enough enzymes, reception sites, etc. to actually store/make use all of the vitamins/minerals consumed.

It's hard to eat a proper amount of food and nutrients in a small window of time. Depending on fiber intake (which decreases appetite), it can be even harder.