You don't know what you're going to get from Jim Harbaugh.

In his Friday news briefing, the 49ers' head coach not only laid a little Ralph Waldo Emerson on us, or so he claimed, he also dropped a little bird-watching knowledge.

Harbaugh was asked about the performance of wide receiver Jonathan Baldwin in Thursday night's 35-11 win over the Rams at St. Louis. Baldwin, acquired in a trade with the Chiefs, caught two passes.

Harbaugh was asked if Baldwin appeared amped up for his first game in a 49ers uniform.

"I wouldn't call it being amped up," Harbaugh said. "I don't know how to explain it; it's just something you see, like I guess a birdwatcher knows the jizz of a bird just by watching it fly. Feel like sometimes I've got an eye for a competitive heart, I see it with Jon."

Not ashamed to admit I had to look it up. Jizz is a word used by birdwatchers to describe the overall impression of a bird garnered from such features as shape, posture and flying style. Jizz is an unidentifiable vibe to which a trained birdwatcher is attuned.

Harbaugh might be the first football coach to apply that term to coaching.

Did Harbaugh pick up that word while birding? Is that how he unwinds? We'll probably never know.

But that's the word of the day, and it can be applied to Harbaugh's football team as a whole, even if the players can't fly. The 49ers' jizz is that they have none.

If you asked longtime watchers for their overall impression of the 49ers, they would scratch their heads. Is this a great passing team, like the one that passed the Packers dizzy in Week 1? Is it a desperately flailing team that can't do much right, like the one that lost to the Seahawks and Colts? Is it a gritty, crunchy defensive team that also can run the ball with alarming ease, like the one that steamrollered the Rams?

What is the jizz of this team?

That's a tough one. Because the 49ers reached the NFC title game two seasons ago and the Super Bowl last season with roughly this same cast, one might assume they are not a poorly coached, dog-meat squad that got lucky against the Packers and Rams.

But the 49ers, to this point, seem un-jizzable. I asked Harbaugh if it might be a good thing to be unpredictable, as the 49ers have been in their two wins.

"Uh, yes," he said, vaguely, "but it's just a necessity this week."

Not sure what that means. Sometimes, Harbaugh's answers flutter off into the sky like wounded doves.

Most great teams have a jizz. The Patriots have long been Tom Brady's attack. Peyton Manning teams are easy to identify by his characteristic wing-flapping. The great Raiders teams could be spotted a mile away by their sturdy straight-up defense and vertical passing game.

One senses that the 49ers aren't being un-jizzable on purpose. They simply are feeling their way, trying to figure out what works and what doesn't, and why.

With the 49ers, you can't get a jizz even on their quarterback. Is he a wild-running read-option cavorter? A drop-back game manager? A roll-out improviser?

Does Harbaugh know? Does Colin Kaepernick know?

Is Frank Gore the fading star now used mostly to pick up blitzes? Or is he the blazing bell cow of Thursday night, rambling for 153 yards on 20 carries, sprinting under defenses like a man leading a jailbreak in a crawl space?

How about defense? The 49ers are all over the map. On Thursday, St. Louis quarterback Sam Bradford, a really bright and skilled fellow, looked as frustrated as you'll ever see an NFL quarterback look, his team clueless and stuck in quicksand.

But the Seahawks and Colts experienced no such frustration. They met a 49ers defense that was like a leaky rowboat in the America's Cup.

The only thing NFL birdwatchers can tell about the 49ers is that they bear the characteristics of Harbaugh, and Kaepernick and Gore, and Patrick Willis and Justin Smith. From a mile away, you can see the potential.

So the 49ers' undefinable characteristic is that you can't write 'em off, even after two wretched games. But you can't pencil them in for a 7-2 start, as some fans and media have done, conceding them the next five wins, because they are more a work in progress than any other elite team in the league.

That's vague, but that's the way it is with jizz. If you could define it, it wouldn't be jizz.

As for Harbaugh's Ralph Waldo Emerson reference, you'll have to learn about that in my Sunday Punch column.