I think Jimbo's VM solution breaks several license provisions - it attempts to get around activation - it has multiple copies installed on VMs, which the EULA does forbid - unless there are valid licenses for each installation (each VM is considered to be a separate computer for licensing purposes).
Use in a virtualized environment. If you use virtualization software, including Client Hyper-V, to create one or more virtual computers on a single computer hardware system, each virtual computer, and the physical computer, is considered a separate computer for purposes of this agreement. This license allows you to install only one copy of the software for use on one computer, whether that computer is physical or virtual. If you want to use the software on more than one virtual computer, you must obtain separate copies of the software and a separate license for each copy.
That is hardly "vague", I think you will agree.
Remote Desktop does allow another user beyond the licensed user for remote access, but specifically one at a time, with other licensing conditions imposed:
Other users, one at a time, may access the licensed software running on this host pc, from any device using Remote Desktop, but only if the remote device is separately licensed to run an edition of Windows 8 or Windows RT.
So if you are using a previous version of Windows, or some other OS on a machine not licensed to run Windows 8 or RT, you can't legally use Remote Desktop to access a Windows 8 machine.
Now if each user had a third party Remote Desktop application such as one of the VNC variants or Letmein, and sequentially viewed the desktop of one of the other users, would this constitute a violation - probably, but who would know?
Looking at Win 8 Pro list of windows features that could be installed, Remote Desktop Web Connection seems to be gone - I am sure it was in Windows 7 Professional and Ultimate editions.