Bioavailability of calories isn't relevant here. There literally is not enough energy in that amount of sugar. Why does it matter if 80% of the available calories is absorbed of 90%?
"Insulin levels - when insulin levels are high energy is stored as fat."
It doesn't matter where energy is stored. 100% of it could have gone to fat.
40 grams of sugar does not have enough calories for you to gain 3 kilograms in 12 days, or 8.5 kilograms in 21 days.
Moreover, if he ate as much as the average American eats, how is it that the average American has not experienced what he has? The guy almost gained 1 pound a day.
Its true that only the average of the three estimates is better.
You won't get a better individual estimate for the baseball player, soccer player, and the football player.