Subfield $w/1 contains restrictions on a reference tracing display; 
subfield $w/2 indicates that a field was formerly an established heading.

Proposal 2007-02 appears to combine these two very different things 
into a single code.  The value added by the new code seems to be 
primarily in the blocking of the use of the reference tracing in all 
of the "usual" contexts (generation of reference tracing display, 
batch heading flips, and so on).  It might therefore be better to 
define the new code in $w/1 instead of $w/2, placing it with the 
other codes that restrict the application of reference tracings.

                 i - Do not display in any reference structure

If we need a new code in $w/2, its definition should be restricted to 
the things that we do with codes in $w/2.  However, it doesn't appear 
to me that we need anything added to $w/2.

We are already suffering under library systems that do not adequately 
support subfield $w.  (At least, I am ...)  I don't think we should 
make it even less likely that vendors will ever support subfield $w 
by having codes that do effectively the same thing in more than one place.

Gary L. Strawn, Authorities Librarian, etc.
Northwestern University, 1970 Campus Drive, Evanston IL 60208-2300
e-mail: [log in to unmask]   voice: 847/491-2788   fax: 847/491-8306
Forsan et haec olim meminisse iuvabit.