As far as I remember, Mike Mentzer also had similar beliefs concerning the idea that a calorie is a calorie as far as nutrition during dieting goes. At least I think it was him, he was making the other competitors pissed by eating ice cream backstage before a show and so on.
And as far as TA's claim that when the body is burning everything it gets, and that it doesn't matter in what form the calories come, I will say it's legit. The part about the thermodynamics is right. A combustible process of the same materials does not create different results. When you have a combustible reaction with any carbon-based material, you will get the same byproducts. Energy does not come in different forms when it's released by combustion. As long as the combustion is complete, it will be the same. Bear in mind, this is based solely on proven theories of energy storage. Everything around us is energy, that's what makes the A-bomb a possibility. The calories are there as a measure of how much energy is released when a certain amount of a material is burned. The calories quantify the amount of energy stored in a certain amount of a certain substance. The laws of thermodynamics does not work differently for different materials. I think TA is right, there are lots of home scientists that makes theories that nutrition is extremely complex when the reality isn't necessarily so. I am not saying that he is right altogether, but when the body burns everything it gets, thus using it as energy, the laws of thermodynamics apply.
Not only that, but when you burn any food, it will become two things after a complete combustion, carbon and energy (in the form of heat). The combustion in the body is no different. And yes, everything you eat are made from the same building blocks. When burned, every food produces the same byproducts! Energy, as we know, cannot be created nor disappear. This means that if there are extra energy created which the body does not use, it will have to be stored. How this is stored is where the nutrition aspect comes in. This is however a totally different story. When the body uses everything it gets in, it's as simple as I have outlined here. There is no other way. Disputing this is disputing nature itself and its laws, which is a very rocky road, indeed.
There is a saying that doing the same thing twice and expecting different results is the definition of stupidity.
Not to mention that the guy who claimed that as fat has more calories per gram than carbs,and subsequently making the claim that a calorie is not a calorie based on said claim, is clearly misled. The calories are the same, there are just more of them in a gram of fat than in a gram of carbs. That should be obvious at this point.