Dworkin's Ironic Appeal to Original Intent

In Dworkin's comment on A Matter of Interpretation, he mildly appeals to original intent of the founders and how they would have wanted the Constitution to be constructed and applied. He claims that at points, the founders were intentionally explicit, and those were when they "intended a dated provision" (122), but in the areas in which they were more broad, they are not procedural, but lay down "very concrete provisions" (122) that still must be applied. He says that "we cannot imagine Madison or any of his contemporaries [...] thinking it appropriate to protect what they took to be a fundamental right" in time-dated terms (122). By nodding to Madison and what the founders were intending when they were outlining rights explicitly or implicitly, Dworkin seems to do a bit of original intent interpretation, himself. Ironically, is Dworkin allowing for original intent interpretation of the Constitution and to what degree? How would he square the theoretical and practical threats of such interpretive strategy that Scalia brings up in his essay? Does Dworkin think that constitutional interpretation necessitates some original intent interpretation in order to derive an effective and faithful interpretive strategy?