You know, I have been following this  discussion, and 
at some point, I became curious about what fsck does differently when it
encounters a filesystem which was mounted with softdep enabled.  So, I
grepped through the fsck sources from today's -current source tree for
"SOFTDEP", taking my queue from the flag referenced in
/usr/src/usr.sbin/dumpfs/dumpfs.c.  Curiously, there is no reference to
that flag anywhere in the fsck sources.  Is this an omission, or is it not
true that fsck cares whether softdep was enabled?
-Brian