Ah, ok that makes even more sense. Frequency boost and attenuation are achieved by Low Pass and High Pass Filters. Even though the transistor isn't conducting normally, your guitar signal is still going through the circuit and the high pass filters that have been constructed into the pedal at the input and the output. Remember, in this circuit, the transistor only acts as a buffer which is done to have a more suitable impedance at the input and output. The Rangemaster is what we'd call an "active" tone control. Though the term can be misleading, as the active part of the circuit ( the transistor or op-amp) usually isn't placed there to affect the signal but to manage impedance. The circuit is working because the signal is still going through the high pass filters which in this case is all you're trying to get out of it. with regard to my first post, if you kept the circuit the same and the same positive voltage but turned the transistor up-side-down, that would give you a square wave (Fuzz/distortion). Germanium transistors also suffer from leakage at the base and emitter junction so that could also contribute to why the signal is passing in an atypical topology.
