Apple 3.5" drive questions

["Charlie" <charlied@NOSPAMbboard.com>]

Recently, through the work of Simon Williams, a problem long held to be a
hardware incompatibility was solved by software.
This made me wonder for the millionth time if software could solve the problem
of reading and writing MS-DOS with an 800k Apple 3.5" floppy drive connected to
an Apple II.

Yes, I know, this is supposed to be impossible.  The hardware is supposed to be
incompatible with writing MS-DOS.

What I don't know is why.

What I do know is that the drive itself (in an Apple IIgs) can read and write
MS-DOS when connected to PC Transporter.  So what is it about the PC
Transporter that is different from the Apple IIgs smartport/IWM?

One guess would be that the Apple firmware doesn't allow for maintaining the
same disk rotational speed.  MS-DOS disks rotate at the same speed no matter
which track the head is on.  Apple disks vary the speed.

Would it be possible to write a driver that could hold the speed steady?

Are there other reasons that the Apple can't read/write MS-DOS?

Charlie