THE SO YOU THINK… format had been running on and off (mostly off) on the Beeb since 1965’s So You Think You Can Drive. Various subjects got covered, but the format remained the same: a panel of experts in the appropriate field were given questions on clips by MC CLIFF MICHELMORE. This one gets special mention due to its heroic pointlessness: the theme was those corny old optical illusions (the triangle-that-isn’t, which of these lines is the longer) which provided work for the BBC graphics department and sleep for everyone else.
