[trolleyhacker]

As long as web designers and developers continue to target imaginary users or themselves, they'll also leave real users wanting more.

Great, you've shaved off 150-350ms of refresh load time. So why does your website take 10-15 seconds to load on my phone when I'm walking about the supermarket?

Get out of the lab. Start testing with real users in real contexts. You'll quickly learn that many of your assumptions about what users want disappear.