This makes no sense to me. Spoken English does not reach 10 words per second even in New York; to hear it, even inwardly, would be to hear a jam of syllables with no respite and hardly any time to parse out the phonemes.
As an Australian crossing the US, I looked forward to NYC because finally I'd be in a place where they talked at a proper speed. But when I got there, while it was nice to not have to slow my speech to be understood, I still found the locals were speaking a touch too slow for my liking.
you're basically denying the definition. echoing in the brain isn't the same as actually getting the muscles in the throat or the mouth to move. It does slow things down but the muscle movement is way slower and some people don't get rid of it.