I would not see why that would be a problem. Quite the opposite, actually: If more users are on the same server, they generate more traffic directed to various destinations and it would be harder to match any traffic to a specific user.
It was possible to scan the 10.xx.xx.xx IP range of the servers a while ago. Some of those computers which were conntected to the same server could be accessed by using the windows file sharing service. That was mostly the affected users fault tho. It was at that time when i figured out what some of the users use this service for. I've ssen some shit in those shared folders (sometimes users even shared whole drives).
I did this for a while and harvested lots of material. Then I reported the security problem to PP.
Unfortunately, its not possible anymore today.