Nobody who has ever been on a high-fat diet will corroborate this. You can't just compare calories like that. As for fibre, I disagree that it is satiating. It

Nobody who has ever been on a high-fat diet will corroborate this. You can't just compare calories like that. As for fibre, I disagree that it is satiating. It may make you feel "full", but that is not the same as being satiated. Your body doesn't tell you to "stop eating" just because your stomach is full of matter that it doesn't actually process. Blood sugar plays a role, as do many other things. If it were any different, diets based around eating lots of high-volume/low-calorie food should "just work", but they just don't.