In Sir TP's books there are several bits which might have been inspired by Monty Python. Here are some after I've just spent 10 minutes thinking.
Rincewind = Brave Sir Robin (Holy Grail)
Igor's speech impediment = Biggus Dickus (Life of Brian)
Pteppic and Sphinx = Bridge questions (Holy Grail)
Ronald Saveloy's translations = Belgium/English dictionary sketch
Getting hit on the head in specific areas to improve intelligence = Getting hit on the head room before argument sketch.