Is is effective at all?
As it commonly known, Windows introduced plenty of allegedly diagnostics collection tools which collect our private data and send this info to MS servers.
Is it efficient and reasonable to block them by means of Windows Firewall? This seems equivalent to putting the cat among the pigeons, i.e. quite useless.
It is naïve to force Windows to protect user from itself. I have a strong suspicion that disregard of firewall rules Windows Firewall will always pass all requests that are treated as "internal" or OS-related. Am I wrong?
Now I use router-level firewall and assume this measure as a most efficient in this case.