Here's an interesting tidbit which came up a few days ago internally at Microsoft which I've never seen documented anywhere. You learn new things every day....
I always thought that there wasn't a limit to the number of concurrent connections to a single Virtual Server using the standalone VMRC client. Admittedly, more than a few connections is obviously going to cause you other problems, most noticably performance, but I never thought there was a limit in the code.
The actual limit was described as being 2 times the number of registered virtual machines plus 1 per VMRC client computer (as tracked by its' IP address). In other words, for a Virtual Server host with one registered VM, the maximum number of VMRC connections allowed from any single computer is 3.
I'll have to try it out, but hopefully you learnt something too!
Oops. Forgot to say - the reason....? To stop DoS attacks from a single IP address.