When you are looking at at list of sessions, you use the filters, sorting, and pagination to get to a particular view. If you click to view a session you lose all that work and need to reapply the filter, sorting, and get to the right page again. Also the search may also be performed again so the result list may even change. With the state of the session list view stored in the URL the browser back/forward and other links would restore the view properly.