[sobriquet9]

The tape delay methaphor confused me. Tape recorders do not record DC or other frequencies much lower than, say, 20 Hz. So that circuit would run into one of the rails just as quickly as the previous cirquit without DC feedback.

[mrob]

It must be an FM encoded tape, which can record DC. There were upgraded versions of both VHS and Betamax with FM audio support (although I expect in practice the inputs were AC coupled).

[sobriquet9]

FM audio does not carry DC either. PLL in the receiver/decoder will eventually catch up with the constant frequency shift.