I did a lousy job of explaining my position on this in the last post I made. I'll start over.
Larry seems to believe that opening all bleeders at once is not a good idea. In the case of these home-style bleeders that you buy for $50-$100, he's likely correct.
Many of these DIYER units will not pump up "safely" much higher than 20 lbs. Some pros say that you need at least 30 lbs to bleed ABS systems.
I've been inside specialty brake shops and have seen them put a car up on a rack, place a bucket under each wheel, connect a "real" presure bleeder, then open up all 4 bleeder valves at once. Alot gets pushed through and afterwards, you've got a rock-hard brake pedal. These shop pressure bleeders pump up alot higher than the $50 DIYER variety.
Using one of these DIYER bleeders that really doesn't pressurize that well, opening all 4 bleeders at once is not going to build enough pressure. I agree.
What this does do is push all of the fluid out in a somewhat equalized fashion. 15-20 lbs of pressure will "flush" just fine. I'll easily use a qt and maybe 8-12 oz. more just to "flush" out the system with all bleeders open.
After the flushing, comes the bleeding. Now I do what Larry suggests, but start with the right rear, then the left rear, then the right front, then the left front.
I'm not made of $$$, but I'm not going to skimp on brake fluid. Pushing a little bit more thru the system in my mind helps to ensure you get a good flush.
Alot of Asian models have proportioning devices and in these cases, you often times use an X-pattern to bleed.