Don,
I do not feel qualified to comment on the current market status and collectibility factor of this particular Specialized. That said, it should be noted that there are some gross misstatements of fact made within the auction listing text itself although these are likely begot of ignorance in conjunction with a desire by the commercial reseller to over hype the relative value of this bike rather than being the result of any malicious intent.
However, your second question provides a perfect opportunity to underscore the potential value of having at least a few of the earlier Shimano catalogs currently available for public scrutiny inasmuch as one now has a few more tools at their disposal should they care to take the initiative to do a bit of research on their own.
The "W" cut tooth mechanism actually predates the full blown Shimano Aero Dynamics concept and was available on both Dura-Ace EX and 600 EX series chain rings (...with a further Super "W" cut version requiring a specialized front derailleur being intended for BMX applications). Basically, Shimano shortened the height of two adjacent teeth at two very specific points on their outer chain rings in an effort to optimize shifting one's chain from said ring onto the smaller chain ring. The principle here being that under heavy load conditions such as when one is standing on their pedals out of the saddle while climbing, the modified chain ring tooth profile at specific shift points reduces the amount of stress inflicted on the outer chain ring, the chain itself, and the front derailleur to the extent that less effort is required to lift the chain from the big ring in order to drop it onto your smaller chain ring, thereby facilitating smoother shifting under these conditions.
You can read all about it using the following convenient links:
http://www.wooljersey.com/
http://www.wooljersey.com/
http://www.wooljersey.com/
Robert "somewhat Shima-Know, ya know" Broderick ...the "Frozen Flatlands" of South Dakota
-----------------------------------------------------------------------------------
>From: Don Wilson <dcwilson3@yahoo.com>
>To: Classic Rendezvous <classicrendezvous@bikelist.org>
>Subject: [CR]Ebay Specialized Aero Prototype
>Date: Wed, 9 Aug 2006 23:03:26 -0700 (PDT)
>
>Aero. Collectibility ramping up?
>What does "WCut" stand for on chain ring?
>280014555729
>Don Wilson
>Los Olivos, CA USA