MK3's Germanium Diode

[bool]

Q2 can pull down so good that there would a DC rectified component develop with signal over time across the 0.22uF cap if there was no diode. This could be remedied with other means, but this is what's on the schematic.

[midwayfair]

All diodes leak when reverse biased.  All of them.

I was exaggerating. The leakage of a silicon diode is too small to be useful for ... basically anything in pedals.

But thanks for the much longer write-up.