Disklabel question (versus bug)

[walt]

Matthew Dillon wrote:
>  ...The reason we don't allow an upgrade
>     is because the FreeBSD disklabel does not have room for 16 partitions,
>     because FreeBSD moved the boot code to be right after the disklabel
>     in order to make room for both UFS1 and UFS2 recognition.
> 
>     With -r the disklabel program looks at the disk directly and is able
>     to discern the difference between a DragonFly disklabel (with support
>     for 16 partitions), and a FreeBSD disklabel.

You may recall that I posted a related question recently, the reason
being that GRUB was suddenly confused by that same FBSD bootlabel.

Just FYI:  I edited the FBSD disklabel (while running DragonFly):
'disklabel -r -e ad1s8'
and made a trivial change (I changed 'amnesiac' to 'FreeBSD') and
suddenly GRUB is happy again!   I can also mount that extended
partition from either FBSD or DF.

This suggests to me that the DF 'disklabel' is somehow more 'correct'
than the FBSD version -- but I don't know just how or why...

Thanks!