I hate to shatter your illusions, but they recorded that for a laugh, it was never shown on TV...
It is hilarious tho!
I think it was for the christmas party, still comedy genius though!
Very nearly right.
Back in the 1970s, before the days of Denis Norden, TV engineers used to record the instances of what we now know as bloopers onto tape and, every winter, edit them together onto one tape and make copies for each other to give themselves a laugh over Christmas. These were not really known outside of the geeky engineers circle, though they could be sometimes be bought at market stalls (particularly Camden Market, which was just round the corner from the TV studios on Hawley Crescent (where the TV-AM eggs were)). Gradually, their presence became known to the actors, so much so that it became somewhat traditional when you messed up your lines to look straight at the camera and say 'Merry Christmas', as you knew it would end up on these tapes.
The logical extension of this was to film special, extra rude, bits purely for these tapes, in the full knowedge they would never be broadcast. The two most famous of these are the Rainbow scene and a special edition of Bullseye, featuring Jim Bowen in a string vest.
http://www.youtube.com/watch?v=Lg_x6aIQ9uQIf you search for Christmas Tape on Youtube you get a lot of these - quite fun to watch (though some are really weak).
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