Fred,
I believe you are correct. Thor does this from time to time when trying new models like the skydeck seen at the RV show. I have seen fiberglass MHs with the names Regency, and Residence as well as the Pinnacle. Most of the Fibeglass "box" Style MH I believe are made at the Dutchman factory, and have the Airstream fabrics, and graphics applied to the same chassis as the Four Winds line.
Take a look at this link to see how the technologiy is spread thru the Thor Line.
http://www.thorindustries.com/script...p=10&year=2002
I understand that AS will be releasing a class C soon. I assume it will just be a diffrent paint scheme and inteior trim of a Four Winds or a General Coach BC motorhome. If you check out the General Coach BC portion of the Thor site you will see that the class "C" motorhomes are already called the Corsair Excella. This was not the way they were named 6 months ago. Hmmmm.....