so right, so wrong

When I make oatmeal, I cook it following the recipe momma found in the magazine Cooks Illustrated. Momma first cooked the oatmeal this way, and we all found it lovely. I, having grown up waking to a huge pot of the Quaker was amazed by this oatmeal. It had a flavor and texture above and beyond the simple additions we made.
I do use this recipe for the cooking. I don't really need to read it anymore, yet I find myself checking up, cooking insurance basically. I haven't ever used the flavoring mix suggested in the magazine, opting for a mixture of vanilla, brown sugar, cinnamon and raisins that I came up with. It's really very good.
It's a pretty simple recipe. Bring milk and water to a simmer, toast your steel cut oats in some butter, toss them in the milk/water and let them simmer. They are supposed to simmer for about twenty minutes, at which point you add salt and let it simmer another ten minutes.
Now here we come to "so right/so wrong." I've made oatmeal a few times. It always seems quick and easy. It is easy, but I have yet to hit the half hour mark. I have never gotten this recipe finished in less than fortyfive minutes to an hour. I wonder if I expect too much thickness. I do like my oatmeal a little thick, but for a recipe to regulary take an extra half hour is just plain . . .I don't know what! The part of this that amazes me is that the oatmeal comes out good. It's never overcooked or burnt by the extra time.
I know that with the weather cooling off, I'll have even more excuses to make oatmeal and figure out where I'm going goofy. I'm determined to figure this out.
On a similar note, when I cook grits, they are done in half the time of any recipe suggestion I've found. Again, they turn out good. If they didn't I certainly wouldn't stop cooking them so early. Just another case of so right, so wrong.