It's a Silicon high gain fuzz face with an added Lpb 1 boost in front. No special Germanium here but it does have an ocean of gain on tap.
I'll write up a full explanation when I have some time to spare
As to the useful range of each pot it's entirely dependant on the circuit design. For example, the useable Bias on the second transistor is 3-3.5V so by choosing a combination of components that results in 3V and 3.5V on either rotation of the pot you end up with knob that doesn't have a minute sweet spot.
Unfortunately I must have been smoking my socks when calculating the Starve/Voltage pot as the useful range is only in the last quarter rotation. Ie useful range is 4V - 9V and turning below 3/4 goes below 4V and kills the circuit. Honestly not in the mood to correct it anytime soon though but no trainsmash either