You better give that one a Google for yourself. Cooking a meatloaf on foil or oven roasting tomatoes on well lubed foil doesn't bother me much, but cooking something wrapped in foil, which is totally different than freezing in foil, your original question, skeeves me out without including the recommended layer of parchment. Why not just include it? It doesn't cost much, and your flavor will not be compromised.
Steve Z.
“Only the pure in heart can make a good soup.”
― Ludwig van Beethoven