Before I had a flusher, I would use a back flush valve and fill the tanks to flush. You are correct, the flow really helps. Three fills and my guages would zero out.
Now that I have a built in flusher I am weary of full tank fills given all the extra plumbing related to the flusher (back flow preventer, etc.) Too many opportunities for leaks for my level of comfort.
I just run the flusher (w/water pressure regulator) for 5 min and confirm clear water coming out.
2016 RAM 3500 DRW 4x4 LB LoneStar Edition, w/Timbrens, Andersen Ultimate 2, Swift Hitch SH04 WiFi Backup/Rear View Camera
2018 Chaparral 360IBL w/TST-507 TPMS, Furrion Wireless Observation System, Progressive EMS-HW50C
2006 RAM 3500 DRW LoneStar Edition
2011 Starcraft 392BHU w/Andersen No-Sway hitch