I don't know how long Shockwave's line gets at SFOT, but for keeping Demon as being retracked, I think that's quite stupid. The ride usually has a walk-on except when the whole park is packed. The line is empty a whole lot.
What they are trying to do (It sounds like.) is to keep the ride for many years because it's so popular. This is like a ride like the Matterhorn, Space Mountain (DL and WDW), and Big Thunder Mountain Railroad. The ride is ageless to the fact that it's always popular no matter if it's 20 or 30 years old. I think Demon has worn out it's welcome.
I don't think it's ageless like Space Mountain where I had to wait 40 minutes to get on with BOTH sides going in a slow season. I really do like Shockwave at that park. The line would tell me if it's ageless or not.
The fact is that it's cheaper just replacing track pieces than to buy a brand new roller coaster. That is what this guy is thinking. He rather save the money on rides, and he rather waste his money by putting up new stupid signs that cost million and millions of dollars. The thing is that you still have to put new rides in the park every so often to keep people coming back.
It sounds to me that the Whizzer is going to be dumped pretty soon at SFGAm if this is happening. If they are going to spend all that money retracking Demon, I really doubt that they will also spend money on Whizzer. Plus, they think they added the kiddie coasters, so they feel the kids have more rides to go on so it doesn't matter.