It is a good question, but it pretty much weighs what it weighs. You could use slightly more spendy material in a frame and never notice it. Most of us probably share a majority of similar parts. Probably the area where the most weight can really easily be saved is in panniers, they can easily add more unecesarry weight from being over featured, than any 2 frames would shed. It also still pays to what wheel component weight, though there isn't a whole lot that can be done about it beyond a basic level of quality.