Plain Meaning and Plain Speaking

I've never given much thought to theories of statutory interpretation. But here's one that comes from being involved in some of the Section Three litigation.

Plain meaning arguments are largely circular. For example, suppose I say that the plain meaning of a statute is X. You respond by saying: "But lots of people said that's not so." I respond: "But you can't consider that because the plain meaning of the statute is X." The plain meaning argument therefore excludes some of the best evidence against itself (statements in the legislature, the context of the statute, subsequent commentary, etc.). Circular.

The only time, I think, that a plain meaning argument is not circular is if we agree on the plain meaning but then argue about whether an exception should be made. Maybe I take the strict view of "no exceptions allowed" to the plain meaning. Maybe you say there is some implicit exception or that equity demands one. But we're not in that case disputing the plain meaning of the text.