I only fill my tank up with water 1 time for the 'stop' step. It works fine.Okay. Fill a tank 3 times or fill a tank 1 time. How valuable is your time?
I also use plain water (the same water I presoak in) as 'stop' when I develop sheet film in hangers. This saves me a whole tank of chemicals that I don't have to set out and maintain 2L of, and store somewhere in my tiny darkroom.