Would that have been that much worse than just running a 3mm cable from the MiniDisk headphone out to the computer's mic/line in? Or was Sony somehow preventing that?
I played around a lot with music trackers (production tool) during this time and often did the reverse so I could hear my productions on other stereos or in the car -- that is running computer output to a tape deck and recording to tape. This was obviously before CD burners were affordable.