I dont feel like my rear brake is dead, but feels like an on/off switch. One thing that will help the rear brake is some LESS powerful brake pads. No, I have not lost it (anymore than usual).
The stock pads are "HH" rated. If you swap to a set of "GG" pads, they offer more range between off and abs kicking in, or lock-up. Galfer "GG" organic pads work well, but leave a lot of dust. DP Pads work better and leave less dust. Then, remove the spring and you'll end up with something good.
I noticed my rear brake got worse when the local shop put the recall guard on. Notice how the two mounting screws for the rear brake mastercylinder have some play in them and if loose, the upper, or lower part of the mc will will move back in forth. Loosen these and set it up where the brake pedal will push straight up on the mc, not sideways.