But you would be limited to MFS and a large drive (20 MB) would soon bog down with all the files in the root.

Click to expand...

For a Mac 512K, the HD20 INIT (on a virtual 400KB system floppy) would provide HFS on the "real" hard disk.

Support for the 128K would be more difficult, as you say, because MFS is not appropriate for big disks. The hard disk work around in the 128K days was to provide a utility that partitioned a large disk into more useable volumes. Only one volume was online at any time, but the user could manually mount and dismount volumes on demand.