How good is Nico Rosberg?

Nobody is in any doubt about just how strong Sebastian Vettel has been in 2011. Jenson Button too has been excellent.

"Jenson's probably been better than you would have expected," says one team principal. "But is that him going forward or Lewis Hamilton going back? Nobody really knows."

That has always been Formula 1's downside. You can only really judge a driver against his team-mate, and sometimes even that's difficult.

Someone could be driving out of his skin, but without a top car he's pretty much invisible.

Take Suzuka. Talk to Virgin team principal John Booth and his appreciation of Timo Glock is obvious.

A no-nonsense Yorkshireman, Booth thinks that Glock is a top bloke and a top-eight driver. Drop him in a Red Bull and he'd be right there, he reckons.

Going to Japan, Glock had outqualified Jerome d'Ambrosio at all bar two races. But then, at a place as challenging as Suzuka, from being a mile away on Friday morning, d'Ambrosio suddenly pipped his team-mate.

"Timo said he was happy with his lap, just a small mistake that cost him a couple of hundredths [of a second] maybe," Booth explained.

"So Jerome's lap was a fabulous effort. And Timo was the first to go and shake his hand. He was bloody great about it! Boiling inside maybe, but he didn't let it show."

D'Ambrosio was a long way away again in Korea, but how many people noticed Japan?

When you consider Glock's ultimate potential, you can't help recall that throughout his time at Toyota he was a couple or three tenths slower than Jarno Trulli in qualifying even if, generally, a more spirited race driver.

Glock has been quietly having a superb year at Virgin © LAT

Not that there's too much wrong with that. In the right circumstances, with a car he likes, Trulli is among the quickest one-lap drivers there is.

So why, over the season at Lotus, is Trulli 14-2 down to Heikki Kovalainen?

If you speak to Mike Gascoyne, the Finn has increased confidence, but it's really all about the Lotus power steering having too much assistance, to the extent that Trulli - the most sensitive driver he's worked with - cannot feel the car.

Kovalainen and Karun Chandhok don't think it's a problem, but Trulli can't cope with it.

These little nuances are everywhere in F1 and are the reason you can't approach performance equations in linear terms. You can't say A is quicker than B, and B is quicker than C, therefore A is quicker than C. Mark Webber, for instance, qualified much closer to Vettel on Bridgestone tyres than he has on Pirellis.

And what at Ferrari, you wonder, is behind the fact that Fernando Alonso had a 10-0 qualifying record against Filipe Massa by the Nurburgring, yet has been outqualified four times in the last six races by the Brazilian?

You might conclude that Alonso lost a little interest upon realising he really wasn't in the championship fight, but his drive at Suzuka belied that.

Alonso didn't look as if he enjoyed being asked in Korea about the recent qualifying stats, but his answer was straightforward enough.

Much more unusual, he said, was to outqualify your team-mate 15 times on the bounce...

He simply hadn't maximised the car at some races and Massa had done some excellent laps.

For me though, the most interesting scenario is at Mercedes. If you polled opinion on the top three drivers in F1, more than likely you'd get Alonso, Lewis Hamilton and Vettel, in various orders.

But how good is Nico Rosberg? Would you not be falling over yourself to sign a driver who had consistently outqualified Michael Schumacher - even a 42-year-old Michael Schumacher - by getting on for 0.5s over a couple of seasons?

"I think Nico is very, very good," says Ross Brawn. "I'm delighted with his performance but where he sits in terms of the ladder, I don't know.

Rosberg, leading Button in Korea is 'very, very good," according to Brawn © LAT

"A race win would make a huge difference to his confidence and I'm very excited about what would develop if we can give him that.

"I do think he's right up there, but until you get these guys in the same car, you never know."

Mercedes has performed in its own little bubble this year. Clearly, it is the fourth-best team on the grid.

Going to Korea it had less than half the constructors' championship points of third-placed Ferrari, and almost double the points of fifth-placed Renault.

Which means, usually, that Rosberg and Schumacher are racing for seventh place.

Clearly, that's a situation Mercedes is not content with. Brawn freely admits the team did not anticipate the way that exhaust technology would develop and that the design of this year's car was compromised.

Elements such as wheelbase, weight distribution and centre of gravity are not where they should be.

The team has recently boosted its technical strength by recruiting both Aldo Costa - technical director at Ferrari until Barcelona - and the experienced Geoff Willis, former Honda tech chief and also ex-Williams and Red Bull.

At Suzuka, Adrian Newey was asked how worried he was about the threat of a Mercedes team boasting five current or former technical directors.

At first we could identify only four: Brawn himself, Bob Bell, Costa and Willis. But there is also Loic Bigois, ex-Prost technical director.

Newey didn't appear to be quaking, though, and said diplomatically that he'd prefer to concentrate on goings on at Milton Keynes rather than developments at Brackley.

Apologies if you're not of a certain age, but one of the older members of the press corps had a football analogy for it.

"You can have five Jack Charltons," he said, "but you won't stop Pele."

Which seemed a trifle disrespectful to Brawn, Bell, Costa, Willis and Bigois, but did made you think. If you really had five Jack Charltons you'd have a hell of an argument on your hands!

Schumacher has started behind Rosberg 12 times this year © LAT

So how is Mercedes going to make it work?

"It's important to have an easy connection between all the elements," Brawn says. "Geoff has to make the aero group, vehicle dynamics group and controls group work even more effectively than it is now.

"Aldo has to make the design, engineering and R&D group work more effectively, and Bob will weld the two areas together."

There are some people with F1-sized egos that you just know couldn't be put together without creating a highly combustible situation.

You find yourself agreeing, however, when Brawn's says: "We've got some pretty reasonably-minded people. If we had difficult people I'd be concerned, but I don't think we do."

The other question that Mercedes' recent recruitment drive has prompted inevitably surrounds F1's Resource Restriction Agreement (RRA).

Brains at technical director level don't come cheap. So how come Mercedes has got five?

Brawn is dismissive of that. Mercedes has increased the head count by two, he says, so there's no real impact on the RRA, and it has plenty of headroom in any case.

Mercedes, he says, is still working up to the limits of the RRA, while 2012 should be the year when the likes of Ferrari, Red Bull and McLaren are coming down to it. So, hopefully, the result will be a more level playing field.

I can't help hoping he's right. I'd love to see those three leading teams become four.

I'd like an answer to the Rosberg question. And you can't help but notice that, on Sundays at least, Nico and Michael have been closely matched.

You wouldn't think a man with seven world titles would have a confidence problem, but the psychology of sportsmen is an interesting area.

Monza, I'm told, was good for Michael's self esteem.

Over time I've looked, slightly disbelievingly, at too many timing screens to believe that it's beyond the bounds of possibility for Schumacher still to move that wins total beyond 91.