> Unprocessed fiber-containing carbs are fairly healthy.

I never said that oats are unhealthy or that carbs are unhealthy. I said that a meal without protein is not the best idea.

My critique was not directed at a particular food item but at the meal composition as a whole.

> I get protein in lunch and dinner, and I don't need my oatmeal breakfast to be protein heavy.

TFA suggests to eat oatmeal for lunch.

> Oatmeal for lunch doesn't make much sense in isolation.

I agree!

I guess, it is possible to make oatmeal for lunch work if you up the protein and somewhat reduce carbs in breakfast and dinner, but way? I think that it is much easier to just make a habit to include a high protein food item in every meal. There is basically no downsides to eating too much protein and there are a lot of potential problems if you eat too little.