Yeah, from what I can gather from the HDINIT binaries, the 2.xx versions take no parameters, for the 4.25 versions you have to add one of the drive types it accepts as a parameter, just as you described.

Testing later, much excitement, very SCSI.

NCR DMV- DEC Rainbow- Siemens PCD- ITT 3030-Oly People- Acorn A5000- Olivetti M20