Yes, it does take quite a while and it's really handy to have a helper, either a pumper or a valve closer. Even with no fluid escaping you still have to close the bleeder valve every time you pump the lever/pedal to purge the lines; added plus is that you also have to keep a sharp eye on the reservoir at the master to keep it from running dry. It'll take some time, twice as long by yourself. Squeeze, open bleeder, lever/pedal bottoms out, close bleeder, repeat.
