as one majumdar (robin) who actually has a clue says, it might be because
"The problem eating Chinese in this country is that the restaurants don't really believe we want to eat anything other than chicken/prawn with cashews and egg fried rice."
so i'm going to ask again: where on earth can you get decent chinese in greater london? (decent by nyc standards; for eg. royal china doesn't even come close to being acceptable).
simon, in all seriousness, before you go all misty-eyed about gods great city or whatever, check out kam chueh or tindo in chinatown next time you are in nyc. and then maybe, just maybe, you'll understand.