mstieler is concerned that if his Boris stomach is 20 and he's eaten 16 fullness, then he won't be able to eat a steel lasagna which has a fullness of 5. He wants to be stopped at 15 fullness unless he already has Stomach of Steel. (Unlike the steel margarita, you cannot eat the steel lasagna if it will put you over the limit.)
It's not a terrible idea, but I'd rather just pay attention if I'm planning on eating a steel lasagna or steel-scented air freshener that day. I suspect a lot of clueless players won't even know why they are being warned since it takes them a few days to get their steel organ.