I think you missed my point. There are a vast array of organic chemicals in biology that all could have been the basis for an eye. And in fact, many have non-eye uses in biology. A photo-reactive system in biology is not particularly remarkable in and of itself, and for there to be one over another seems to be pretty arbitrary to me.
My objection is to the idea that "eyes" are remarkable from a biochemical standpoint. I would actually assert that the neural systems behind the eye are for more intriguing and difficult to explain. I don't have a lot of context for Schroeder's position, I only find it odd that he focuses on one of the least remarkable aspects of the whole thing and tries to paint it as more remarkable than it actually is.
What I'm saying is that Schroeder is going to great length to say that the bear dances badly and ignores the remarkable fact that the bear dances at all. I don't really have a beef with Schroeder, just with his odd priorities and perception of "remarkability".
Nebullis and I have been mulling around Pax-6 and the import of it. You might be interested in the articles linked and partially excerpted at post 184.
Evidently what astonished the researchers was that (emphasis mine)