I think grits might be OK, but I don't know for sure. I know that couscous is allowed, and it is a pasta type thing. Also other grains that are somewhat processed are allowed, like bulgur and rolled oats.
Grits are maybe more highly processed since they are soaked in lime or lye to remove the outer coating of the corn kernel, but the process is similar to making masa for tortillas and those are allowed mostly because you usually eat them filled and only eat two at the most.
I would think that if you ate grits once a week it wouldn't be a problem, unless it causes you to not lose weight, or you have other health problems. My husband eats grits often because he likes them, in the beginning he didn't use them when he was losing weight, but this was only because he thought he couldn't eat them on the McDougall plan. After I told him he could eat grits, he began eating them. He's stopped losing weight because he now cheats often, I don't think it has anything to do with his eating grits!
Since you are MiamiGuy and not MiamiGal, you can probably get away with eating something that is more processed than some of us girls do.