I threw this together:

http://usotsuki.info/thedosescape.zip

This contains a program I wrote to cram DOS 3.3 into 256 fewer bytes (by 
disabling format and revectoring a couple patches) so that ProDOS need not 
be overwritten.  It's a SYS file, and runs from ProDOS 8.  (I also tested 
it under GS/OS 5.0.4)  On the DOS 3.3 side of the disk is a file RETURN TO 
PRODOS, which pokes in the MLI call for "quit", then executes it - proving 
that ProDOS is still fully available.

It's useless, but eh.

-uso.
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