As anyone who has been on the receiving end of that kind of one-upmanship from Garret can testify (I recall the humiliation of mixing up in his presence the dates of Cardinals Richelieu and Mazarin) we can be fairly sure that he was not often caught out again.
Then again, Garret’s UCD degree was in French (first class honours), History (first class honours) and Spanish (second class honours – that was, of course, before grade inflation). For the rest of his life, Garret’s favourite holiday destination was France.