Someone tells a joke based on a prompt. This would be your Genesis block. Then everyone else competes to tell the funniest joke based on only that and the new prompts from the audience.
Repeat until you have an ongoing, hilarious comedy routine that cannot be edited after the fact without being found out because that would ruin the whole routine. It just wouldn't be as funny.
Someone tells a joke based on a prompt. This would be your Genesis block. Then everyone else competes to tell the funniest joke based on only that and the new prompts from the audience.
Repeat until you have an ongoing, hilarious comedy routine that cannot be edited after the fact without being found out because that would ruin the whole routine. It just wouldn't be as funny.