It should be your goal to put the garbage man out of business with your frugality. I am in the middle of a job change and move to another state. Now I think we have something to discuss. I agree with all of your points, and if true then I need to question the restaurant's concept. I would think that few patrons will go to an upscale quality restaurant that specializes in foie gras and truffles to eat cod.
Proper recipes are vital as is the updating.
Yield factors are important or you get the wrong idea of your actual purchase price. Francois, just from general experience I don't think that an upscale operation serving the kinds of quality products you do can pull off such a low food cost.