long and useless

I don't think it matters who the story was about. Eveyone that played the game knows that particular piece of the past wasn't just about Vincent, Hojo, and Lucrecia. I think making it seem that way was inappropriate and pretty much says all the important stuff that happens pre-game isn't all that important unless it involves Vincent's relationship with Lucrecia. I guess my main point, though, is that I can see absolutely no reason for not including Gast, it seems to have been done arbitrarily without any real purpose for the story.