"How much did Santa's sleigh cost? Nothing, it was on the house." The joke is met by groans that echo through a warehouse in Lambeth, London. We're at a joke-testing session with Talking Tables, a ...

The key to a good Christmas cracker joke is not whether it is funny but whether it can elicit groans around a dinner table, experts say "How much did Santa's sleigh cost? Nothing, it was on the house.

"How much did Santa's sleigh cost? Nothing, it was on the house." The joke is met by groans that echo through a warehouse in Lambeth, south London. We're at a joke-testing session with Talking Tables, ...