In order to understand why this feature has been removed, you must understand why it was used in the first place. The first main reason is to be able to connect to session 0 on the terminal server (the console) because certain applications and services must run in session 0 in order to function properly. The second reason is to connect back to an existing session on the physical console.
Why are these things not a factor anymore? First of all, improved application compatibility ensures that legacy applications that need to operate in session 0 will install and run in sessions other than session 0. Secondly, because the physical console session is never session 0, you can always reconnect to your existing session without any trouble.
Although it may seem as a bit of a shock initially, there really is no need for access to session 0 anymore.
Chris Sanders is a network consultant for KeeFORCE, one of the most popular network consulting firms in western Kentucky. Chris is the author of the book Practical Packet Analysis as well as several technical articles. His personal website at www.chrissanders.org contains a great deal of information, articles, and guides related to network administration, network security, packet analysis, and general information technology.