This is getting more difficult than it needs to be.
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After an intial pass of clean fluid and then some bubbles coming through on the rear passenger's-side caliper, we all of a sudden got tons of air -- more air than fluid -- coming through. Eventually I switched over to the other side, and was just getting tons of air most of the time.
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The master cylinder reservoir has a internal dam ( 2 when there is a clutch master cylinder port ) to prevent one circuit from draining all the fluid if another leaks. You probably ran out of fluid on the side you are bleeding.
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My dad was pumping the pedal for me, and I was closing the bleeder each time I told him to let it up (in fact, before I told him to let it up), so that shouldn't be an issue?
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Closing the bleeder ( lightly ) before the pedal is released is the proper method.
Here is the easy way to bleed brakes , half of it will even work with one person and generally produces good results.
Gravity bleeding
Fill the master cyl to the normal level , leave the cap loose but sitting on the MC to prevent splashing.
Slide a ~ 18" long piece of vacuum hose on the bleeder screw, direct this into a pan. The end does not need to be in or on the bottom of the pan. The hose creates a siphon effect and keeps fluid from making a mess.
Open the bleeder screw. if fluid comes out let it drip for a bit. If no fluid, leave it open and pump the pedal a few times until you get some fluid but do not press more than 1/2 travel. ( more than 1/2 travel can damage seals as they ride across dirt if the MC is old )
Let the fluid drip until you don't get any bubbles coming out. ( the bubbles will look sort of like soap bubbles / discontinuity in the stream. )
Close the bleeder and move to the next brake.
The above works fine with one person and produces good results most of the time especially if the MC was not run out of fluid. Even then it works well enough to move the car around.
A trick to getting more fluid out is to finger tighten the bleeder so it acts like a check valve allowing a bit of fluid / air to come out but won't draw fluid when the pedal is raised. With this , a single person can operate the brake pedal.
A step above this is the 2 person bleed. Do the vacuum hose trick and let fluid flow. Lightly tighten ( just over finger tight ) have the person in the car press the pedal _SLOWLY , ONLY ONCE and NOT WITH HIGH PRESSURE_ ( hand pressure would do ) , once they have pressed the pedal, open the bleeder then close it once you get a spurt of fluid and / or air. When the fluid runs clear, tighten the screw. The bleeder seat is tapered so it does not take much to generate a seal.
This technique will surge fluid through the system bringing trapped air with it that didn't come out during gravity bleeding.
If the brake pedal is pumped rapidly, that can aerate the fluid causing more difficulty in clearing the system.
Lastly, in a real pinch, do the gravity bleed, close the screw then compress the caliper pistons, this will force air to the top of the system and out the MC. This works better with worn pads or careful observation of piston position with a pad removed and brakes pumped to extend the piston.
A modified method is to leave the brake line loose , compress the piston, re tighten and pump the pedal to extend. Sometimes the bleeder screw is stuck and the above 2 are the only way to get air out.