Much of this talk is related to Rear Disk set ups.
You are using the standard stock Rear Drum set-up. Use the distribution block. This is the way the Smiths designed their braking system to work, and it does just that – It Works.
Don’t screw with something you do not need to. I have the stock set-up (rear drums), and with the pedal arm mod, and the distribution block, I love my brakes. I can lock them up with moderate force, the fronts will lock first, and it tracks perfectly straight under emergency stopping requirements (been tested