A year or two ago, the sketch writers were waiting for the Deputy Prime Minister to address the Committee for the Environment, Transport and the Regions. As he passed by with his vast environmental, transportable and regional entourage he scowled at us and said out of the side of his mouth: "Come to pour another bucket of shit over Parliament, have yer?" I said: "We only bring the bucket, John."
That's how I tell the story, anyway. I prefer not to remember whether I made the remark then or on the following day's staircase. But I can, if I want, work myself into a state where I do believe that I made that perfect rejoinder with perfect timing.
Whatever the facts, the way I tell the story can be defended because, look, I didn't use the word "reply". I said "I said". I didn't say when I said it. Purists may quibble it only has a poetic or dramatic truth, but actually, in fact, the statement is literally true as well. I did say: "We only bring the bucket, John."
And to prove it - there it is in print right in front of your eyes. It is poetically, dramatically and literally true; that's pretty good for a story that isn't true.
This all came to mind listening to the Prime Minister telling us about last week's EU summit (if you'll admit to not knowing there was an EU summit last week I will too).
Teddy Taylor asked him whether he would "oppose wholly and completely the invasion or bombing of Iran by America, Israel or anyone else". As you may know, Israel has recently taken delivery of "bunker-buster" bombs from America; Iran is ploughing on with a nuclear programme; Israel once bombed Saddam Hussein's nuclear power station (which is partly why he didn't have any weapons of mass destruction - but that's by the way).
The Prime Minister replied to this important question with words he has used before: "Nobody is talking about invading Iran. It's absurd."
I regret to say, the first word that fell into my mind was: "Christ". From the Prime Minister's answer it may be deduced that he has had intelligence that there's going to be a strike on Iran and sooner rather than later. If you want to bet on the price of oil reaching $65 a barrel, I'd start with a million dollars a point.
Returning to the Deputy Prime Minister: he followed on from the Prime Minister. He had come to the Commons,wading through the rubble of his career, to make a statement on the North-east's vote repudiating his offer for a regional assembly.
It was a triumph. It was democracy. It was part of a great strategic policy to bring freedom and power to the people. It was a thorough vindication of postal voting.
He was criticised but Mr Prescott gave as good as he got. That was so depressing a thought I had to leave the chamber.