I always have a nice clean piece of wood for under the pedal. My "helpers" are usually not real drivers but will help. Having them push the pedal to the block and tell me "down" and they hold it there. then I close the bleeder and when closed say "up". and they let the pedal return up and say "up" when it gets there, and then I open the bleeder and say "down" and repeat the process until I am happy with that wheel. Over stroking the mc will definitely cause you a lot of problems with getting air into the system. Way better to use shorter strokes and have to do it many more times than to try and do the pedal three or four times and call it good.
You said your self you started with empty lines so that will take a lot of fluid. Then you have the fluid that is used up with the bleed process. And making sure the reservoir stays full, or you get to start all over again bleeding the mc.
I can't see how the booster is causing the pedal to have slack but I'm no expert. I just think you aren't being patient or during the bleed air is being reintroduced some how.
Give it a few days off and work on something else if this is frustrating you that much. A clear head and plan of attack is way better than getting upset and throwing stuff.
You said your self you started with empty lines so that will take a lot of fluid. Then you have the fluid that is used up with the bleed process. And making sure the reservoir stays full, or you get to start all over again bleeding the mc.
I can't see how the booster is causing the pedal to have slack but I'm no expert. I just think you aren't being patient or during the bleed air is being reintroduced some how.
Give it a few days off and work on something else if this is frustrating you that much. A clear head and plan of attack is way better than getting upset and throwing stuff.