Depending on the polling method / frequency, he could have created some problems for them. As to automatically popping people off the stack registration is often a complex issue where I want the CS101 10am-12am session vs CS101 8am-10am session, but only if I can also move my Math 10am-12am to TR at 2pm - 5pm etc. (And that's a simple change vs some of the optimizations I did.)