I am using C.
Unfortunately (perhaps is that really the right word?) it now seems to perform as i expect, so I am afraid I can't give an example at this moment! What I can say is that I have a workspace with multiple projects. I did have each project set as 'taq with project specific tag file'. I have now changed this to 'tag using workspace tag file' and done other manipulations on the project/workspace. Probably not much help.
You have confirmed from your response that the behaviour is unexpected, so if I see it again I will preserve the workspace/project to see if I can generate a test workspace/project for you.