One of the things that drives us crazy about preseason NFL predictions is that the so-called experts (us included) tend to take the safe path, assuming that the good teams will still be good — and likewise picking only one team from the AFC (usually the Bengals) and one team from the NFC (usually the Lions) that will surprise us all.

But history tells us that there typically will be 50-percent turnover in the playoff field. 

So this means that, of the 12 teams that made the playoffs in 2007, it’s a safe bet that six of them won’t return in 2008.  And that they’ll be replaced by six that didn’t make it a year ago.

Is it a guarantee?  Hardly.  But it’s hard to ignore the fact that so many teams typically don’t get back to the postseason field, and that so many failures find a way to succeed in the next season.

Recognizing this reality, the challenge then is to try to identify the six teams that won’t make it back to the playoffs, and then to peg the six non-playoff teams that will fare far better in 2008.  And this spawned an idea for a three-part series of SportingNews.com columns — one that lists the six playoff teams from 2007 that won’t return, one that lists the six non-playoff teams that will make it to the postseason, and one listing six teams that didn’t make it last year, and won’t make it this year.

In pegging the half-dozen who’ll fall out of the playoff pack, I tried to be objective and fair.  In so doing, I’ve now ensured that I’ll receive a stream of unfriendly e-mails from Steelers fans and Packers fans from now until the date that either or both teams are eliminated from postseason contention. 

And if either or both teams qualify for the playoffs, I just might never hear the end of it. 

Of course, I’m used to taking a foolish bold risk.  I predicted that the Steelers wouldn’t make the playoffs the year after they won Super Bowl XL, and I didn’t hear the end of it . . . until the Steelers didn’t make the playoffs the year after they won Super Bowl XL.

Anyway, the full list of teams is right here.  We don’t expect to get them all right.  But if we accept the premise that six of the twelve teams won’t get back, it’s inevitable that fans of six teams who were spoiled by a playoff run a year ago will be disappointed in 2008.

Even if one of the teams that might not make it back played in the Super Bowl.