Would it be completely unpossible, in theory, to add allocate-on-flush
to vfat? I don't see a reason why, it's just a driver semantic and not
a disk data structure semantic...
I'm looking at a USB stick copying gigs of data and thinking about this.
I have doubts there's any real world advantage, although in the same
theory you could backport AOF to ext3/2 or you couldn't.