Earlier quoted context omitted.
Yeah right. Just wait until a user visits fast.com and unthrottle their connection for 20 minutes. I strongly suspect some ISPs already do that with speedtest.net.
Note to self: set up cronjob to ping speedtest.net and fast.com every 10 minutes, just in case.
https://github.com/sivel/speedtest-cli
If you are going to setup a cronjob/service for it, I suggest using the --simple flag.