[kazoomonger]

> it's pretty obvious the second half is false

It's really not. As I said above, people are not identical. Yes, evolution doesn't produce perfectly consistent results. However, absorbing nutrients is the direct foundation for the only thing that matters in the process of evolution: reproduction. You can't reproduce if you die from lack of nutrients. Given how much of humanity's existence has been staving off starvation and famine, any improvements would be heavily selected for, and would quickly spread.

As an extreme example, if you could survive on an apple per day, the next famine that rolled around would leave you pretty free to repopulate with your superdigestive genes, since most everyone else would be dead.

> You went to the trouble of mentioning CICO and then totally forgot about CO!

I don't really understand the point you're trying to make in this paragraph. Even if some people "run hot" or they have some magic gut that lets them survive on an apple per day or whatever, it's still a fundamental truth that if they're fat, they're eating too much. Yes, someone can exercise more or whatever to change their output, but the reason they're currently fat is because they're currently eating too much.

> It's self evident that CICO is true. It's just completely worthless for providing any insight. Very much a thought-terminating cliché as originally described.

Yes, no, and no. As described above, there really are people that think "I eat just an apple a day and I can't lose weight!". CICO is a baseline for saying "no, that's impossible". It's not a thought-terminating cliché, it's making sure that everybody is on the same page of accepting basic science.

[Zababa]

> Given how much of humanity's existence has been staving off starvation and famine, any improvements would be heavily selected for, and would quickly spread.

If that was true, shouldn't we have evolved to hibernate at some point?

> You can't reproduce if you die from lack of nutrients.

You also can't reproduce if you can't run fast when a wolf is hunting you. Those muscles are going to take some energy even while not running away from a wolf. I think you're trying to reduce evolution and reproduction to a single variable, which is a mistake.