NetBSD-current's fsck does the former.  Every version of fsck ever
      shipped with NetBSD does/did the latter.
   
   ??  I didn't notice it doing so... maybe I just missed it.

didn't notice which ?  netbsd 1.0 does not have a "clean filesystem"
flag implimented, but -current does.  you won't see this in 1.0 because
it's not there.

   Should I try a -current?  I'm really not into being on the bleeding edge.

i recommend it;  there are several performance increases, and a much
better scsi sub system (it uses the same as most of the other ports).

but be sure you follow the "rules" of upgrading, if you are doing to
do it by compiling your own (check the mail archive for the
current-users list on ftp.netbsd.org for these rules).

.mrg.