"The Ironic Dao" is a term used by Brook Ziporyn to describe the Dao of Daoism as a response and contrast to the Dao of Confucianism and Mohism. Most all I relate here is derived from his introductory discussion in his Zhuangzi, and must necessarily be both brief and 'unscholarly' (in that I am not a scholar).
The 'Daoist' Dao is ironic in that it completely turns the previously understood meaning of 'dao' on its head. Confucius was principally concerned with the harmonious functioning of society and gave little thought to metaphysics. His Dao was a "guiding (dis)course", a fixed set of principles which, if followed would lead to this harmony. It was a Dao which is studied and spoken ("to speak" being one meaning of dao). In this context, there are many daos.
The Daodejing, on the other hand, explicitly dismisses this spoken Dao as not being the true Dao; for Dao stands for that which would seem to 'exist' beyond our ability to form any verbal description of it. Dao is now understood metaphysically (although if left in its simplicity, it is an extremely spare and content free metaphysics). The Dao that can be spoken (the Confucian and Mohist daos) is not the "Eternal Dao". Nor is the Daoist dao.
But the Daodejing does not dismiss the spoken daos altogether; these are Dao as manifest in human activity. And though these daos cannot approach to Dao, they are, nonetheless, "the same" with Dao. Daoism recognizes both dimensions of Dao, the Nameless and the Named, and, although the latter cannot be said to properly represent the former, it is, nonetheless, its expression in existence. Dao is ultimately understood as the unifying One, yet is also understood as being expressed in the many.
All of these references to Dao can lead to confusion if not understood in their historical and conceptual context. When I quote Confucius on the Dao (that it is at hand and not afar, for instance), it must be understood that he meant his understanding of what leads to harmony in society, not the Dao which cannot be spoken. Still, we can quote him in this regard because we understand that his dao was an expression of Dao.
We all have a dao, whatever our beliefs, disbeliefs or unbeliefs. The distinctly Daoist dao is one which is informed by an understanding of Dao as Nameless. In this, Daoism prescribes a particular dao of manifesting Dao, a dao which leads to harmony. But because Dao is Nameless, Daoism recognizes that no dao can fully express it. Daoism is able, therefore, to prescribe a certain way of expressing Dao, on the one hand, and yet acknowledge the validity of other daos. There are still many daos. There is more than one way to skin (or pet) a cat.
(A word on using the Daodejing as an exemplar of Daoist thought: Though I do not see it as pre-dating the Inner Chapters, I suspect that Ziporyn and others are correct in assuming its core ideas (quoted within it as aphorisms) do.)
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