Possible Clues:

• It's irrelevant to the professional scholar
• Theoretical only, like Auden's graffiti?
• A rat leading its relatives the last first, it's learned
• It's not practical for a rotter to have the mice in bits
• Fellow's a rotter, torturing mice
• In Mecca, aid demented professor
• Theoretical or scholarly - often not practical
• Scholar - of no practical relevance
• Don - of no practical importance
• Of theoretical interest only to lecturer