Yeh you can see this if you compare the first American versions of The office which copied the British one almost totallyThere is definitely a gap between the British and American humour. I was talking to an American girl about someone who couldn't find a set of office notes that were right in front of his eyes and I said to her " does he need a white stick" she had no idea what I was on about, when I change it to "is he blind" she got it? Subtlety, sarcasm and Irony are lost on them, the joke has to be REALLY obvious.