>I'm not a chemist or a food manufacturing engineer, but my educated
>guess is that it would be extremely difficult if not impossible to
>create a "Protein" bar which is low in carbs without the use of soy
>protein.

I make protein bars in my kitchen at home all the time.  Mine are
low carb, come in a variety of flavors, contain no preservatives or
artificial ingredients, contain no whey, no wheat gluten, and no
isolated
soy protein.

They're called "pemmican."

-Bruce