when you nose-clip you want high-calorie foods, not low-calorie foods. The more calories the better.
You could use noseclipping to eat the less pallatable healthy foods, such as high-fibre foods, but combine them with lots of calories by including mayonnaise or cream cheese, for example. Bean sprouts with mayonnaise, maybe making a kind of coleslaw out of your favourite raw vegetables. Or even combining fruit and vegetable into one meal. After all, it doesn't matter, because the taste sensation is skewed.
Here in the UK we had a diet in the 80s called the F Plan, which proposed that eating extremely high fibre foods means the body becomes less efficient at digesting calories (effectively, a higher percentage than usual ends up in the toilet pan). The trouble is that high fibre food is dull, and that made the diet a trial. Yet with nose-clipping it becomes much more possible.
If nose clipping does work for AS then I think there's huge potential for a very clever diet plan that could borrow a little from each of the proven diets (high-fibre, low GI, high-protein etc). The only drawback is that I suspect there's an increased risk of choking. You might want to teach your family the Heimlich Manoeuvre first