Seems like it would approximate ancient conditions our bodies evolved to cope with. Especially the part about working hardest right when you're hungriest, then you get to eat. That sounds like a hunt!
Yeah some studies show exercise in a fasted state increases adrenaline and human growth hormone production, so it's kind of like getting natural steroids. :) It also helps train your muscles to burn fat for energy which is great for endurance (you have far more fat in your body vs. sugar for energy). Great info here: https://intensivedietarymanagement.com/fasting-and-exercise-... and http://leangains.com/