Mark Twain was once involved in a discussion about storytellers who annoyingly interrupt themselves to ask the listebers whether they have heard the story they are telling before. Twain told of a conversation he had had with actor Henry Irving.
Irving asked Twain whether he had heard a certain story. "No," replied Twain, prompting Irving to begin telling the story. Halfway through Irving again stopped and asked Twain whether he had heeard the story before. No" replied Twain more emphatically. Near the climax of the story Irving stopped and once again made the same request.
"I can lie once, I can lie twice for courtesy's sake, but I draw the line there. I can't lie the third time at any price. I not only heard the story, I wrote it."