How about the argument that higher sugar intake causes you to be more hungry, therefore making it easier to eat less calories on a low suger (high-fat) diet. I know it's an entirely different argument from the "keto magic" argument you are ranting against, but do you object to it?

Firstly, it doesn't come up in proper trials (eg http://www.ncbi.nlm.nih.gov/pubmed/17413101).

That's part of the general Taubes carbs-insulin hypothesis; that insulin affects satiety (the feeling of fullness, or no longer wanting to eat).

As I said above, there are more hormones involved than insulin. For example, one very influential hormone is leptin. It has a profound affect on appetite and satiety; but we still only understand it poorly.

And leptin can be affected by all sorts of factors. Sleep deprivation, even small amounts, really play merry hell with it. Next time you're running on fumes, you may notice both that a) you're starving and b) your ability to resist the temptation to eat anything is greatly diminished.

And so on. The body is more complex than the thermodynamic equation, but ultimately that is enough to control your mass. The additional details are worth introducing as and when they are necessary (and a good dietitian will do that), but not before. People are very good at giving themselves excuses and, of course, analysis paralysis allows them to forestall any real change.