Interesting issue. However, I think that MS code activation is quite sophisticated. I had installed MS Outlook on 2 computers (desktop and laptop) which is allowed, but had some problems with my desktop. I had to re-install it a couple of times and finally got a message saying that I had tried to activate it too often and had to call MS to get a special code. I was lightly grilled and finally got my code.
However, how would that work with pirated software if 50 people are trying to activate with the same code? Is XP less stringent than some of the more expensive MS Office software?