Do Americans find it as hard to distinguish between, say Scots and Yorkshire as people back here do to tell someone is Canadian rather than from the USA?

.............

If it was just swallowed T, that would be tolerable. It's when it spreads to other consonants in the middle of words that it gets over the limit of comprehensibility. K, even G and P. Some people seem to dispense with consonants almost entirely.

I've sometimes sat on the train hearing a conversation, and speculated what strange foreign language it might be (the next but one station is Stansted Airport) and then the penny drops, it's English. And I still can't understand it. And these aren't immigrants.