Eric,

okay, what you suggest is just that this is a normal behaviour after a 
*bad* crash, and not related to whatever hidden upgrade of the FFS code. 
I'll make a backup of whatever is important and start over.

That leads me to a question: if I reformat the slices, is it better to 
choose ffsv1 or ffsv2 or is it irrelevant for relatively small partitions?

Thanks a lot,
Vincent