Re: Dodgy legal ground..
"When you blindly clicked through to merrily install your 'free' gift from M$ you agreed to the T&Cs to allow them to spy on you and alter settings at their whim. All keystrokes on Windows 10 belong to M$."
Which may well be an "unfair contract" since they effectively pushed the upgrade on users and have made it almost impossible to say no by nagging you every 30 days to install Win10 even when you say no. Actually, you can't even say no. You can only defer saying yes.