[ghaff]

I remember back in school, for some purposes, there was definitely a serendipitous aspect to finding related books in open stacks that were near the one you went to find. However, this was back when you were mostly limited to a physical card catalog as a search tool.

I don't do a lot of research (that a library is useful for) these days and what there is is mostly in journals and the like. But, in general, I find that with electronic searches of library catalogs it's probably less important to discover things accidentally by physical proximity. (And a lot of big libraries aren't/weren't open stacks anyway.)