I feel that I have not explained clearly enough the Studio features that we use. We often export classes to XML files. Similarly, we import XML files, compiling them as classes during import. I didn't mean to imply that this was done simply to transfer classes to other namespaces or servers. Rather, it's a way to archive classes as XML files. (We don't use a source control system.)

We use the Find in Files utility to determine the classes and other files in which a given string exists.

I mentioned the Namespace variation of the Studio Workspace pane because that is the arrangement of files (classes, lookup tables, message schemas, etc.) that we most often use.