As important as how quickly your website responds to request for content is how quickly your organization responds to requests for information and assistance, whether for a new sale or to support an existing customer. It does not do much good to get a form fill "thank you page" 100ms faster if the inquiry takes a day or more to get a response.
Amazon would probably tell you otherwise.
Is that why all of their Fire series devices come with an app that connects you to a live customer support representative in video chat?
I think they actually support my contention: Amazon allows you to talk to real people very quickly.
8 updates, listed in reverse chronological order, at he too of the article.