Comment by kvdveer

There are a lot of valid critiques already, but here's another:

This technique will have to allow for over-all slow connections. This connection latency could be caused by over-provisioned office connections, torrents, bad gsm reception, cheap internet or a cheap device.

What prevents a client from strategically delaying specific requests, to simulate a slow device in the target geography. AFAIT, this would be indistinguishable from the scenarios mentioned above.