“We avoid sincerity until it is absolutely necessary” is spot on. A generalisation, sure, but it’s the truth that everything revolves around.
I think we’re better at applauding success than we used to be but, still, keep your success to yourself, or maybe just hint at it, rather than display it.
I love the British sense of humour (being British, of course) but much of the comedy I really like is American – TV comedy from the US, when it’s in a form that is palatable to Brits – often seems razor sharp, and scientific in its tightness.
Gervais’s Office here in the U.K. is deeply British in its humour, but is still not everyone’s idea of funny.