Hi there.
Here's my 2c worth. Just read this thread and it looks a little different from my less WB savvy perspective.
To me it looks like an electronic fault in the controller/cable. Simplest level, drive doesn't seem to be receiving a signal from the write pin..pin 23 i think. It's probably more complex, like a lightly fried chip, but it's worth checking components associated with R/W operations.
I'm unfamiliar with the internal workings of the amiga disk wrangling utilities, but usually fdisk style utils read the disk contents, work on the RAM copy and then when you are done, splat it to the drive. I'm not sure whether it checks.
Oh, is there corrupt data afterwards or no change?
There are also many other possibilities including databits or addressbits going missing. anyone ever had a disk write garbage, or just become a bit bucket for writes.
Theres all sorts of weird and wonderful combinations for problems.
So just eyeball it. Look for problems, especially corrosion in the connectors. Oh and any unusual heat dissipation.
