I'm happy to report that my 4Kn drive is now performing as expected. Originally, I low level formatted the drive using sg_format to disable Protection Type 2 which appeared to work normally. This time around, I re-formatted the drive using openSeaChest_FormatUnit. I re-ran all of the commands above to check sector sizes and such and cannot find any differences, so I really don't know why the drive is behaving differently after formatting with openSeaChest versus sg_format. It could just be coincidence. Nonetheless, I'm happy to declare victory. Thanks very much for all the help.
