|As I read the EULA, it doesn't matter how many instances of the OS reside on the Machine the OS is licensed to. It only matters that you have a Valid license for the version you are using.|
Windows is tied to the Motherboard Hardware not to some arbitrary number of installations. You can only USE one instance at a time on any given machine. Which instance is up to you.
That's just my interpretation of the EULA.
There is nothing to learn from someone who already agrees with you.