I agree with with a lot of what you're saying; however, I asked my OSO before I contracted about this and he said that the ASTB is looked at more as a pass/fail qualification. It is not a major selection factor that the board is going to look at. They way he put it, the board is mainly looking at your leadership experience/potential, PFT (and history of physical activity), your GPA, and everything else. Could the ASTB be looked at? Yes, but it is not going to play a significant role, especially if the rest of your package is good. Honestly, I don't really think it matters. Just try to get the best score that you can get and work hard on the rest of your package.
Also, its just my opinion, but I would just throw out there that a lot of what they want to see isn't the quantitative stuff (PFT, GPA, etc). The board wants to select people that they feel have the potential to be a successful leader of Marines. With how competitive it has been it is easy to get caught up in the numbers, but the other stuff matters as well. Hope this helps someone out there.