Of course, if you do, be prepared for a lot of software to break because it's hard-coded to use "C:" and not actually use the APIs or environment variables to f

Of course, if you do, be prepared for a lot of software to break because it's hard-coded to use "C:" and not actually use the APIs or environment variables to find the system drive location, user files location, etc. A lot of what gets blamed on Microsoft is really down to poor third-party software. Microsoft goes to extremes to keep that stuff running.