The last time I asked for a book in Book on optics in curved space-time , the question was closed as being 'primarily opinion-based'. David Z explained clearly why it was not appropriate and suggested I reword it. He said a change in the book policy might cause a shift in the present policy. I see many questions here being closed for similar reasons. But each question carries a unique story and a context. Every book recommendation given still constitutes a definite answer to the question. In spite of the question being closed, I still see people responding in the comments.
While I can appreciate where the moderators are coming from, I have found that other SE websites like the Math SE are more welcoming of such questions. The book list is not really sufficient. While I imagine most people can get what they want in this list, it is insufficient for more specific questions.
I enjoy collecting valuable (both pedagogically and historically) works in science and mathematics (even more than reading them :D). So sometimes my requirements might be specific. So I have to ask, if the requirements are not easily met by the book list, is there anything I can gain from Physics.SE (without compromising the specificity of my requirements)?