is the difference more than 5% - 10%? because there are differences between the efficiency of energy consumed during digestion of the different macros (Fat, Protein, Carbs). That could be the obvious difference here. Otherwise, it's not a red herring.

For example, I've heard that if 100 calories is eaten of protein, you may only digest 80 calories, arbitrary number, but it may differ than carbohydrate's 90 calories per 100 eaten.

I would like to give you a succinct answer, but I am not as well spoken as Robert Lustig, MD, a Professor of Pediatrics in the Division of Endocrinology at University of California, San Francisco, and the author of Fat Chance: Beating the Odds against Sugar, Processed Food, Obesity, and Disease.

Is a Calorie a Calorie? Processed Food, Experiment Gone Wrong

Presented by Stanford Health Care

https://www.youtube.com/watch?v=nxyxcTZccsE

That video you linked is focusing more on "health" than "weight loss", which should be considered different. If there's somewhere in that 1:40:00 long video that he says calorie counting doesn't work, please time-stamp it.

Counting calories itself is an exercise in accounting. How would it help with weight loss?

try out my earlier comment "Try Calculating your TDEE (at sedentary) and eating 500 calories (accurately) below it for 12 weeks and come back, you'll weigh 12lbs less. I don't think that's a red herring."

Get back to me in 12 weeks.

The thing is it's not possible if the metabolism is broken.

It's a bit like saying "If I double my velocity every hour, will I reach 1000000mph?" Yes and no.

The human metabolism is a dynamic system with feedback. You can't sustainably eat 500kcal below TDEE for long periods of time because the body will turn down your TDEE to the minimum. For me that's around 800-1,000kcal/day. I've stayed weight stable for 2 months straight eating around 1,000kcal/day. I've also LOST weight eating over 4,000kcal/day (very different phase of my life, obviously).

CI and CO are not unrelated and you can't change one and expect the other to stay fixed.

Out of date. Watch this instead: https://www.youtube.com/watch?v=zumrAR5qHX0