

It has been done already!

In the UK the Atari ST box was shipped with 360K disks in the first few
years and then later 720K disks. In order to make life less complicated,
many freebie disks on mags were double formatted like this. Side 0 of the
disk had 360K on it and could be read  by any ST. It also had a flip-side
program. This would swap the sides around so that side 1 became side 0.

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