An agent can add a user directly from the ticket screen.
Lets say that an agent is taking a phone call from a customer and needs to open a new ticket for that customer.
Instead of navigating away from the ticket screen, the agent can simply add the new user directly from the new ticket screen. The Add User link is located in the Ticket Details metabox (usually located on the right hand side of the ticket screen).
Ticket List In User Profile Screen
Admins with access to the user profile screen can now see a list of tickets for the user directly in that screen. Clicking the ticket # will take you directly to the ticket screen.