Mmmm. Thank you for sharing the data point. I wonder if there is a database with the success records of each game, measured after each game's conclusion? That would seem to be one way to settle it.

(And, psssst, I'm slowly working on populating exitgames.co.uk prior to a grand opening, complete with a UK puzzle huntevent calendar. Mum's the word for now, but hopefully not for long!)