The San Francisco 49ers are an overtime defeat away from being 8-0 for the season. They are 4-0 on the road, own three fourth-quarter comeback victories and lead the NFC West by five games with eight to play.

They are also quite likely playoff pretenders, K.C. Joyner told us Thursday, making waves on the NFC West blog.

Jim Harbaugh would work even greater wonders with the New York Giants, K.C. Joyner contends. Geoff Burke/US Presswire

"I think Jim Harbaugh will win a Super Bowl before he's done coaching the 49ers," Joyner said when I followed up with him over the phone. "I just don't think this is the year."

Fair enough. Still, I thought the "pretender" label was a little harsh, but I also knew Joyner does his homework.

NFL teams run about 30,000 plays from scrimmage in a given season. Joyner studies every one of them. He has charted every pass play since 2003 and all but a partial season's worth of running plays since 2006 for the books he publishes annually. Whether or not he's wrong about the 49ers, he figured to have some interesting insights.

Mike Sando: You said the 49ers' defense has beaten up on bad offenses and fared worse against good ones. You also watched the 49ers hold the Detroit Lions to season-low averages for yards per pass (4.4) and yards per play (4.2). You also know they've gone 30 games without allowing a 100-yard rusher. What about that Detroit game?

K.C. Joyner: It's Megatron and that is their offense. They are not a good running team. Brandon Pettigrew is a solid tight end, but he's not Antonio Gates or anything. Nate Burleson, OK, you can deal with him. Titus Young -- it's all good, but not dominant. They are not the Eagles when Philadelphia is on with so many weapons. San Francisco is beating the teams they are supposed to beat. The big genesis for my piece is the strength of the division. Teams coming from the worst divisions rarely do well.

Mike Sando: OK, but the 49ers have played only one division game this season. They are 6-1 outside the NFC West.

K.C. Joyner: I'm not knocking the 49ers. They've won outside the division. But the idea is, more than likely, if you have not been built to beat the stronger teams, you are not going to raise your level. The Bears teams of the 1980s didn't win more because all they had to do was beat the Vikings. But teams like the Redskins had to raise their level to beat the Giants.

Mike Sando: The 49ers' remaining schedule is third-easiest in the NFL, but they do have measuring-stick games against the Giants, Ravens and Steelers.

K.C. Joyner: If they beat the Giants this week, color me impressed. If not, this is a team that has not played the toughest competition. They are playing much better with a great coach, but this is not going to be the '81 49ers. They are not at that level.

Mike Sando: The Giants did not impress me against Seattle or Arizona. Are they any good?

K.C. Joyner: The Giants are good. They play to the level of their competition. They will step it up against a good team. If Harbaugh were coaching the Giants, they would play at that level all the time and win the Super Bowl. They still might, but that is the problem with the Giants. They should have stomped Miami, but barely won. They always do that.

Mike Sando: The 49ers' running game would seem to have a favorable matchup Sunday. What stands out when you look at San Francisco on the ground?

K.C. Joyner: When they get decent blocking, they are exploding for big yards. I keep a stat called "GBYPA" or good blocking yards per attempt. There's a series of rules that I follow, but basically we're talking about plays when blockers do not allow defenders to disrupt the play, when a running back has an opportunity to get yards. The 49ers have 98 runs like that and 907 yards gained on those runs for a 9.3-yard average. That is an elite number. Chris Johnson, during his 2,000-yard season, averaged 9.0 yards per carry on these runs. The entire 49ers team is doing better than that. LeSean McCoy is at 8.3 this year. Matt Forte is at 11.2, which is an awe-inspiring number.

Mike Sando: The run blocking hasn't been consistent enough, but you're right about Frank Gore in particular maximizing what is there. Harbaugh marveled this week about Gore's ability to contort his body in ways that let him get through the slightest openings in a defense. One more thing before we finish up. No discussion of the 49ers would be complete without covering Alex Smith's play. What do you see from him?

K.C. Joyner: I've seen only one bad decision from him all season. By bad decision, I mean plays where the quarterback makes a mistake with the ball leading to a turnover or near-turnover. Last season, Smith made these plays 2.5 percent of the time. He is at .5 percent this season, which is a Tom Brady-like number. They have taken a guy who was a good safe passer and gotten him to play a little better.

Mike Sando: One of the points you made in your "pretender" piece said the 49ers' relatively conservative approach to pass offense wouldn't be good enough in the playoffs, most likely. This is the one aspect I'm most interested in monitoring when the 49ers face teams such as the Giants, Ravens and Steelers. Could be something for us to discuss later in the season.