Countdown used a specific Oxford dictionary as "Dictionary Corner" contained (usually) an employee of OED and a celeb. In due course, Susie Dent was employed by the programme, so she appeared on most of the programmes. http://wiki.apterous.org/Episode_1572
refers to the pincer incident, but I can't find a Mr Pincer either. I may have got it wrong, (misremembering a chat with Dave years ago), as they also disallowed words as you wouldn't get them alone, so "pincer movement" would be considered a single phrase, so "pincer" didn't exist alone, and the gripping tool "pincers" would be plural only? We did get a list of rules before recording. They now use an electronic version of the dictionary.
My first opponent punted "moaniest" in the first round, which was disallowed, as "moaniest" wasn't specified in the dictionary. More recently, they decided that any one-syllable adjective ending in "-y" can automatically have "-ier" and "-iest" as the comparative and superlative. Luckily, I got "minarets". Looking back, http://wiki.apterous.org/Episode_3176
I recall feeling rather stupid that "amortise" and "atomiser" were possible in Round 1, (which they told us) and I missed both again in round 6... My opponent was unlucky to have "moaniest" disallowed, especially as it was round 1 and probably put her off for several rounds.
There were always discussions of this type. E.g. "Mauve" is a colour, but can a shirt (e.g.) be "mauver" than another one, or be the "mauvest" shirt in your wardrobe? I guess "Scrabble" had the right idea, producing and selling a dictionary of their own.