The reason why oatmeal is not suggested in the morning is due to the phenomenon of metabolic drift that I've discussed before. It would it water down the reactions you might have to foods, since it strengths the immune system. Take it easy. I usually suggest nothing more strenuous that a fresh air walk for folks on the elimination diet. The problem is that if you have aches and pains from exercise it will be difficult to distinguish the same from a reaction to a food during the testing phase.
Food allergens create inflammation.
The elimination diet not only contains hypo-allergenic foods, but it is also decidedly 'light' and would favor the metabolic needs of an Agriculturist metabolism. Note that it contains some foods on the recommended as well as some foods for the avoid for each metabolic type to give some 'buffering' action. I have considered creating two elimination diets. One for each metabolic type. The problem is that if you guess wrong and go with the H-G elimination diet and you are actually an Agriculturist, the diet would not reveal anything.