Ukcol, thanks for posting that Horowitz and Hill excerpt.
I notice the H&H example current-driven demodulator had two diodes in a voltage-doubling mode. The voltage-doubling demodulator was in and of itself claimed to have lower distortion than a conventional diode, as for example shown in this article from Radio-Electronics for 1959 October:
RE 195910 p.58 AM Demodulator.pdf
Heathkit used the voltage-doubling AM demodulator in quite a few of its hi-fi tuner models, and also in some communications equipment.
Cheers,