I think I need to recapitulate, while this is going on.
If you put in the normal 640K DOS Plus Boot disc, FastBoot doesn't do anything, allowing the normal 31-second loading sequence to proceed.
If you try a 720K DOS disc, the 80186 boot system can't understand it. If you force FastBoot with D-BREAK using the 720K DOS disc, it has a go but decides it can't read it.
So you've guessed what I'm doing now, eh?
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