As said confirm that the air is out of there then you will know if there is a proportioning problem (or not). I grab a helper & have him pump the pedal vigorously several times then on the next down stroke (with perfect timing) I open the bleeder which this helps get the agitated air out of there & in some cases the caliper needs to be pulled & tilted just right (in your hand/still connected) for the air to rise to the top. It like the air vent in the Egyptian pyramids, the air vent exit (bleeders) dont need to be exactly at 12 0'clock but where the passage meets the bore needs to be at or close to 12 0'clock. Put a block under the pedal so the cups dont go past their normal wear area & it helps him control the pedal movement better.