It looks like it is saying that you first have to have an XP pro disk with a valid license. Where is the gain?
# Obtain genuine Windows media and a corresponding product key for the eligible version of Windows for downgrade (see next section for eligible Windows versions).
* The media should come from a prior legally licensed version from the OEM or Retail channels.
* Additionally an end user, who is licensed separately through Microsoft Volume Licensing (VL) programs, may provide their VL media and key to their system builder to use to facilitate the downgrade on only their systems.
# Insert eligible downgrade version of Windows media in the CD drive and follow the installation instructions.
# Type the product key.
* If the software was previously activated, you will not be able to activate it online. In this case, the appropriate local Activation Support phone number will be displayed. Call the number and explain the circumstances.When it is determined that the end user has an eligible Windows license, the customer service representative will provide a single-use activation code to activate the software. Please note that Microsoft does not provide a full product key in this scenario.
# Activate the software.
John