what is it about british humour?

To rephrase: what is it about classic British humour? American comedies seem to thrive on stupidity and duh-ness (yes, there are American comedies that accomodate elements of cerebral merit, so this is not a blanket observation). British comedies, at least the ones I like, seem to employ a reserve, and an unrelenting misanthropic cynicism, which finds a poor parallel in the physical humour of American comedies. Brit comedies also employ better literary references. I seem to find common elements as I enumerate my old favourites: Yes (Prime) Minister, 'Allo 'Allo. And then there's Fawlty Towers, which features the reliable John Cleese as the rudest, most unfriendly, misanthropic, maladroit hotel manager in the universe. {the germ for this post is my recent rental from the public library of the DVD containing the episodes of season II}.