I agree, the 6mppa number would only be achieved if the runway at SOU was 2,500m and there was no BOH 30 miles down the road.
3mppa forecast at BOH is more achievable given the above arguments and the 2mppa forecast at SEN is even more achievable given the large core population that will surely seek to fly from there.
PS i hear teleparty has been banned for disrespectful comments on other threads. Yippeeeeeee