Let me explain for you. Watching a play in slomo takes longer than in real time. Watching slomo in slomo would be even longer. so when he says it was long, it is because 3 seconds would look like 20 seconds or something like that. See the joke there, It looked like a like time because he had it for 20 seconds. He knows it isn't real, it was a joke.

But see you are jumping on him thinking he is dumb for not seeing the play the way you did, and you think I am dumb for asking you about it. Kind of ironic isn't it.