As I'll report more fully, we had what I thought was a wonderful moment of this at TravCon. I picked a Steve Ellis game to play in mainly because it was Steve but also because it was monks in a monastery. When it came time to hand out the character sheets I was delighted to find and couldn't resist volunteering for the librarian monk.
Poor Steve. Not sure he had quite expected all the questions about what books there were, what categories of things there were (fiction? Banned books?), whether they were chain or borrowable etc, how many? In what space?
He and the other players were very patient and let me loose for five minutes and then we got on with the plot. :-)
But yes, I take your general point that it's not generally a good idea.
tc