[kragen]

It's definitely an entertaining idea! And you probably could have made it work.

RAM would have been a cheaper and probably more reliable edit journaling device than an 8-track tape. It would survive warm boots unscathed where you had to reboot the computer after hanging it, failing only if your edits were lost to a power outage, and you would test it all the time, not just when the computer crashed. A battery-backed CMOS shift register memory chip, maybe about 2048 bits in size, would have solved the power loss problem, but keep in mind that a lot of these early microcomputers were so bare-bones they didn't even include a real-time clock, which is the other thing you want the battery for.

In 01996, Chen et al. at UMich proposed just such a (non-battery-backed) RAM journal to avoid losing written data in kernel crashes in https://web.eecs.umich.edu/virtual/papers/chen96.pdf, "The Rio File Cache: Surviving Operating System Crashes". They reported that it worked surprisingly well, and it enabled them to increase the durable transaction rate of their spinning rust filesystem by about three orders of magnitude, if I recall. And of course NetApp have been shipping FAServers using that approach (with battery-backed RAM) since day one, also about 01996.

Tim Paterson's blog I linked elsewhere in the thread has some comments about quantitatively exactly how fast different floppy systems used on 8-bit computers were.