The long straights of Shanghai circuit are playing beautifully to the double DRS system of the Mercedes, confirmed legal yesterday after Lotus's protest. It looks that way during qualifying simulation anyway.
Last week Ross Brawn spoke of how he was hopeful that the drop in competitiveness from qualifying to race days of Australia and Malaysia was nothing more than set up problems and largely unconnected to the DRS system. He was putting it down to poor choices to do with tyre management. But the pattern in second practice here suggests the shortfall of race pace is still very much there.
Michael Schumacher was fastest of all in qualifying simulation, the system even more potent around here than in Malaysia, thanks to the huge length of the back straight. But in race trim - without using the DRS system at all - both Mercs dropped quickly off the pace, on both types of tyre.
Schumacher conducted a nine-lap run on the medium tyres late in the session, while team-mate Nico Rosberg did an 11-lap run on the softs. Out at the same time was Lewis Hamilton's McLaren on the softs. The Merc appeared to generate instant tyre temperature - tricky in the cool (15-deg C) conditions - and Rosberg's first lap was 1.2s faster than Hamilton's. However, the McLaren's tyres appeared to be in the perfect window by the second lap - and the Merc's appeared to be already degrading.
Hamilton's run was only for six laps and so his times may well have been flattered by a lower fuel load - though the two teams usually make very similar fuel level choices. Whatever, on the second lap the Merc was 0.5s slower than Hamilton, then 0.7s slower, 1.2s slower and 1.4s slower on successive laps. In qualifying simulation Schumacher's Merc was around 0.1s faster than the McLaren.
Rosberg did not get in a good lap during his qualifying simulation, and the pressure is very much on him after major lock-up errors in each of the previous race's crucial Q3 laps.
The degradation rate of the medium tyre on the Merc was less bad than on the soft - but still worse than the McLaren's on the soft. It all points to a possible pole by Merc - but yet another swift fall backwards during the race, where the McLaren - running with a new floor and diffuser and detail changes to the front wing - appears yet again to be the gold standard.
Jenson Button had a less happy Friday than Hamilton. Running a lower downforce set up, he spent a lot of time changing suspension detail. He eventually found a reasonable race balance, but was picking up a lot of extra understeer when he switched to the soft for a qualifying simulation.
Lewis Hamilton was one of several drivers locking up over the bumps © XPB
Like pretty much everyone, he suffered a few lock ups over the bumps approaching turns six and 14. The lower than forecast track temperatures combined with the enhanced bumps appear to have had an adverse effect on cars that have lost much of last year's rear downforce to the regulations.
In order to keep the cars balanced the front wings are being run with less downforce than in 2011 - all conspiring to make front locking up a problem. It's going to be crucial in both qualifying and race to avoid this as the Pirellis are extremely intolerant of it.
Red Bull back-to-backed the original exhaust system with the more forward-sited later one. Ever since the newer one was introduced in the final two days of winter testing, Vettel has not been as happy with the car's balance - specifically matching up its slow to fast corner handling traits.
Mark Webber on the other hand is adamant that the newer system is an improvement. So each driver was given their preference today and from the look of the times, there seems very little difference between the two layouts. Vettel put together a better qualifying-style lap that was 0.2s quicker than Webber's and actually on the same tenth as Hamilton. But on the longer runs Webber appeared to have a small but consistent edge.
It's always tricky trying to read too much into Red Bull vs McLaren race pace because of the differing fuel strategies the two teams usually choose. On the surface, Webber's Red Bull was marginally ahead of Hamilton's McLaren after six laps each on the soft tyre. Given its closeness in one-lap pace to Hamilton, despite a straightline speed shortfall, the RB8 again appears genuinely quick.
Fernando Alonso is unlikely to repeat his Sepang victory if it's dry on Sunday © LAT
But just not the dominant machine of last year.
As in Malaysia, Lotus could not seem to unlock the potential of the car in terms of one-lap pace but it looks capable of a very fast sequence of laps - maybe even the best of all. But if it's starting from the fourth row, it's going to be difficult to convert such performance into results.
Ferrari looks set to again fight over the crumbs of the lower Q3 order with the likes of Sauber, Force India and Williams, though Fernando Alonso's race pace in the cool conditions was quite respectable and certainly better than either Mercedes. The forecast has the weather warmer on Sunday - and if true this will almost certainly hurt the car's competitiveness.
Even if a Mercedes starts from pole, this race looks set to be fought out between the McLaren and Red Bull drivers. That's if it remains dry. But that was the forecast for Malaysia too - and look what happened there.