Google doesn't show me this widget, but the speed test on Google Fiber's website is just a frontend for Ookla's Speedtest I mentioned. So I suspect that the widget does the same or similar stuff. I don't know for sure though.
> It tests using a node 200+ miles away (they tell you where)
"200+ miles away" from your physical location doesn't mean "outer internet outside your ISP". It doesn't mean "far away from your ISP's network" either.
For example, some mobile carriers may operate country-wide, but route everything through Important Central Connector To Outer Internet™ in the capital city. Consequently, internet services think that user's phone is in capital city.
So while you see "City 200 miles away" as a test node, it may actually be the closest one because your ISP's network structure adds these mandatory 200 miles. ISP's internet access node and speed test node may be literally across the street or in adjacent server racks.
Not saying that it is certainly the case, just trying to explain why words on test screen may mean things different from the ones we assume.
> AND it actually shows slow numbers when the pipe is slow. Turns out Amazon Video was the culprit
From your words, it didn't show you slow pipe. It showed you regular one that was busy with streaming video.
Also, ability to watch streaming doesn't necessary indicates actual internet speed since streaming services like Netflix can provide ISPs with the hardware for caching [1] and streaming from inner ISP network. Not sure if Amazon does that though.
> Amazon Video was the culprit, somehow using 80% of a 100Mb connection for a single stream...
Amazon streams with a higher bitrate than most of the competitors. 80 Mbps isn't that surprising given that Bluray disks have 40 Mbps bitrate for 1080p video. With streaming you also preload some video ahead in a buffer, so hitting 80 Mbps is completely normal.
