It goes on to say that having more muscle helps burn calories when active even more so. I agree with your assertion that extra muscle burns off extra calories 'at rest' may be imply more than its actual results, but I don't see that it makes it a flat out myth.
More muscular people who exercise burn more calories than less muscular people who exercise the same amount, and burn more calories at rest than less muscular people at rest. That statement evaluates to True. That it isn't to the degree you like doesn't make it False.
May as well say you burn more calories drinking cold water because your body has to heat it up. This is a little meta, but I think if you say something that, while technically true, causes people to behave/believe in a certain manner unwarranted by the facts, you're functionally equivalent to lying. Anyway, point taken, "lie" was not the most tactful choice.
I get where you're coming from. I just always notice that when I'm in shape, it's much easier to keep in shape. Whenever I allow myself to fall out of shape, it's much harder to get back in. Perhaps it has nothing to do with the argument at hand, but that probably contributes to my bias.
Of course you're right to debunk the argument on its face, but I do wonder how much more caloric burn you get from the muscles you have during exercise, and whether that doesn't make up for it.
It goes on to say that having more muscle helps burn calories when active even more so. I agree with your assertion that extra muscle burns off extra calories 'at rest' may be imply more than its actual results, but I don't see that it makes it a flat out myth.
More muscular people who exercise burn more calories than less muscular people who exercise the same amount, and burn more calories at rest than less muscular people at rest. That statement evaluates to True. That it isn't to the degree you like doesn't make it False.