It’s happening again. Redskins fans are falling victim to Optimism Creep, that feeling that everything, finally, may be all right. Symptoms usually appear after a preseason win. One of the worst outbreaks came in 2002, when the Redskins put up 38 points in their opener against San Francisco in Steve Spurrier’s debut.

If not treated, Optimism Creep can easily turn into Reality Fatigue Syndrome, when the season turns into one long burgundy and gold slog toward mediocrity. That’s what happened in 2002, when the Skins, despite their preseason start, finished 7-9 and out of the playoffs.

Friday night’s win over Pittsburgh was impressive, it’s true, but mostly because the Skins didn’t stink. That’s the bar now — not stinking, not finishing 4-12 or 6-10, their results the past two seasons.

It’s hard to blame fans for their OC. It’s beyond their control, and it happens to fans of all teams, in all sports. It just hits harder among fans whose sports immune systems have been weakened by years of going through OC, then RFS, and then starting the cycle all over again. Sadly, that group includes Redskins fans.

I’ve suffered OC and RFS myself — my OC usually sets in around January, the RFS in March — but my RFS was temporarily treated in 2008. Redskins fans have had almost no relief from the cycle since I moved to town; it’s hard to blame them for their current affliction.

So the OC leads them to e-mail and post on message boards and call radio stations to crow about the stellar play of the offensive line and Tim Hightower. (They don’t mention the defensive backfield, hoping that the return of their starting safeties will solve that problem.)

They even begin to accept the idea that Rex Grossman might be their starting quarterback after all, and they forgive him for predicting an NFC East title. (They aren’t ready to believe that one yet; that symptom comes later, if they win another preseason game and if Chris Cooley’s knee shows improvement.)

Even when Jason Reid tells them their quarterback will not be Grossman, but Beck, they’re still okay with that, even though they’ve really seen Beck throw only on YouTube, where his highlights vie for attention with cats who play the piano and have mustaches reminiscent of Hitler’s.

Mike Shanahan must also be an OC sufferer as well. How else to explain the continued presence in camp of perpetually injured wide receiver Malcolm Kelly? He has logged more miles on a bike than Lance Armstrong, but the bike, like his NFL career, is stationary.

And how else to explain Beck as the putative starter despite his complete lack of a pro resume? Because he shines in film review? Seriously? So did Pauline Kael, but she never started for the Giants.

There is no known medical cure for Optimism Creep or for Reality Fatigue Syndrome. One winning season would mitigate the disease, but not wipe it out. Only repeated success — a return to the success of the glory days of the franchise — will put both OC and RFS into remission.

Until then, we can’t help the sufferers. We can only be patient with them — and hope it’s not catching.