Fiesta was a flop because there wasn't much to do there other than shows. Good shows, but still shows. When SF took over, they added FIFTEEN RIDES in ONE SEASON. That will boost ANY park's attendance. It wasn't the management style that got them going, it was the ride package.
As for closing it, I think they will have major probs at SFOT if SFNO, SFAW, and SFFT are all closed. SFOT is already too crowded most weekends (when outof-towners visit) and dumping the crowds from those other parks in there will make the SFOT experience miserable. Spend 12 hours at the park on a Saturday, ride 6 rides. Whee.