Interesting article, @swamidass.
However, truth be told, I have always wondered why this argument (the origins of homochirality) is though to be such a strong pro-ID one by ID proponents. My reason is this: Regardless of the model or pathway by which life originated, catalysis enters the picture very early on. In my opinion, the most important classes of catalysts are going to be those that resemble, or are, polymer-based. In other words, rather large macromolecules that work by binding substrates on surfaces.
It turns out (and anyone can confirm this with some modeling clay) that surface-based catalysts (this would include polypeptides) are necessarily stereospecific. Thus, once these mechanisms start to come into play, stereospecificity and ultimately homochirality are inevitable. Indeed, were I trying to make pro-design argument, then purely racemic mixtures, and not homochiral ones, would be the hallmark of design. This is because natural mechanisms cannot, by themselves, give rise to such mixtures in any sort of OOL-relevant sense. (Again, this is granting the obvious instance that catalysis is central in the origins of life.)
