Back in the late 70's there was a new OS, CP/M 80 Version 2. Included in the BIOS support was a simple and very effctive sector blocking / Deblocking algorithm. The default support was 128 byte sectors on the common disk environment, 8 inch floppy disks. With the sector blocking and deblocking code, any size of physical sectors could be supported. On my Morrow Thinker Toy's double density controller, I was able to go from 256 byte sectors to 1024 byte sectors gaining a nice huck of space. In 1981 I worked for Micromation and had a chance to play with a 14 inch winchester hard drive, which had a huge 20 megabyte capacity. It had a "fixed" 512 byte sector size. After a little messing around with the drive, I found that the drive really could support larger physical sectors. I went from the 20 megabyte tot disk size to 1024 byte sectors and go another 6 megabytes for a total 26 MB out of a 20 MB drive just by enlarging the sector size.