Andrew Sullivan vs. the New York Times on Federal Marriage Amendment

Need some help here from those who like intricate constitutional law and logic problems... This morning, Andrew Sullivan goes after a New York Times story about the proposed constitutional amendement to "protect" marriage. Sullivan complains that the NYT reporter misses the fact that this amendment would make even civil unions for same-sex couples unconstitutional. The key clause in the proposed amendment, for Sullivan, is that in italics:

Marriage in the United States shall consist only of the union of a man and a woman. Neither this constitution or the constitution of any state, nor state or federal law, shall be construed to require that marital status or the legal incidents thereof be conferred upon unmarried couples or groups.

Sullivan argues that this would make same-sex civil unions unconstitutional. I'm not so sure (and do keep in mind I think this amendment is a really bad idea - my point is just that AS is misreading this element of it). What that second, tangled, sentence says to me is that state or federal courts cannot read into the US or any state constitution a requirement that marriage or something like it be extended to "unmarried couples or groups" where such a requirement is not there explicitly. This seems to me to be an attempt to prevent the "imposition" of civil unions or full-blown marriage for same-sex couples through what the right perceives as "judicial fiat." It leaves open that states could allow civil unions through constitutional amendment or some other legislative process that would expressly permit it. The key phrase is "construed to require." That phrase seems to get at the right's fear of judicial imposition of civil unions and still allow a legislative enactment, which it, I guess, could live with.

Sullivan seems to believe the language of the amendment would also prevent the enactment of civil unions through the state legislatures, in contrast to the NYT reporter saying that route is still available. My reading is that the NYT is right and AS is wrong. Am I crazy? (Well, I'm no crazier than folks who think that a constitutional amendment that cuts same-sex couples out of marriage is a good idea...)