Unfortunately it's also the case that: simple fact recall -> less need to cheat. Non-trivial calculation -> more need to cheat. There are other reasons to not

Unfortunately it's also the case that: simple fact recall -> less need to cheat. Non-trivial calculation -> more need to cheat. There are other reasons to not use simple fact recall type tests, of course. Like actually testing transfer. But, in support of what you said: I went to Uppsala University in Sweden, and all exams were 6h long and happened in a giant special-purposed exam hall with 6 feet spaces between each desk. Cheating by communicating was a lost cause and even if you could, the amount of info you'd need to transfer to make a dent in a 6h-long test would be way too large. I don't recall anyone trying to cheat, but if it was to happen, it would have been done by adding notes to the bible-sized book of tables and formulae that we almost always were allowed to use.