If a test logs a user in it should log that user out. Particularly if itthen goes on to delete that user. Failure to do so screws up tests thattry to access the website, logically enough.
adding a simple example tclwebtest test case that creates a test user and logs him in over HTTP, requests a web page, and then teardowns the user. In order to do this I copied over some procs from etc/install/tcl to tclwebtest-procs.tcl. The procs in etc/install/tcl should go away as we have tclwebtest fully integrated in acs-automated-testing