ddrescue shenanigans

Recovering a Failing WD My Passport with GNU ddrescue I recently remembered that I have an old 1 TB WD My Passport Ultra external drive that stopped working. At first it looked bad: the drive would not mount and diskutil list would hang while it was connected. The drive spun up normally, the LED blinked, and macOS asked whether I wanted to allow the USB connection. That was enough to start investigating.