Self Service - Login

We always have our employees login to self service. This gives us the ability to tie policies to active directory groups. Eg "it admins have a bunch of tools tied to them" "employees my have access to licensed software, and ad different vpn"

If your in an externally authenticated environment like AD etc... Then is makes sense to have sign in, even if it's single sign on, it gives you the option of controlling Self Service policies based on groups within the Authentication system.
It really depends on your environment though, we are an educational institute so we have quite clear differentiation between what a student versus a staff member should be able to do to a computer.

Our environment is currently only used by a single department, so I've not enabled authentication and so it keep the users happy. Just wanted to hear what others were doing and if there were any con's or security issues