Lyle believes, as best as I can tell, (based on what he's posted on his blogs in in his forums) that, in the presence of adequate macronutrients and micronutrients, food quality is pretty much a non-scientific notion and that the paleo critique of grains, dairy, etc., is also silly and pseudo-scientific. It's what Michael Pollen critiques as nutritientism (although Pollen also believes that anti-grain, anti-dairy types are wacky as well).
IMHO, Lyle's the go-to guy for fat loss, and in the contexts that he recommends them, eating your Fruit Loops can be sound nutritional strategy. You want abz with minimal loss of lean tissue, Lyle's the guy.
If you are looking for good, solid patterns for life long living, there are a bunch out there, some pre-industrial but post-agricultural, and some pre-agricultural, and none of them contain Fruit Loops.