Bob, my mind is a bit cloudy, as usual, but we simply changed the old format to entice racers to compete at the outlying tracks. Mission, Spokane, Port Orford, etc. have never acheived the same level of sucess as PR and PIR, and the new points system awarded those who ventured to the "less traveled" venues.
It used to be 5 points for first, or 8 points if someone else in your class showed up. So to win a championship was pretty easy if you just ran the I-5 series, collected the big points and ignored the tracks where you knew there would be little participation. Now, as we all know, if you don't go to Mission or Spokane, or soon to be ORP you won't be in the points hunt in most cases.
Losing a potential 25 points for a win, or even say 18 for a 5th place is just too much to throw away for most drivers looking to take a podium spot at years end. It seems to work, and has for quite a few years now. I hope it won't be messed with too badly, but I suppose I should check the rules change proposals, because I apparenlty missed this one.