What an absurdly stupid idea. Ethics aren't levels that "support each other", nor is there such a thing as a person without meta-ethics -- just because you don't see them or can't understand them obviously doesn't mean that they have none. What would you draw from when considering one's moral system in such a case (such as the 10 commandments/suggestions linked to in the article)?

An analogy is for clarification -- it helps a person picture the ideas that you're projecting. You can't draw conclusions from an analogy unless they've already been drawn outside of the analogy, otherwise you're using the analogy for a dishonest intent.

Let's picture this argument in the article as a house, and the foundation is its main argument that ethics is like a house. But if that's not true (and there's no reason to believe it is), then the whole argument falls apart. Would you like a picture of a house without a foundation to see what your argument looks like at this point? Is the absurdity of this approach at least a little clearer now?