maybe they dont want to risk failures they didnt do much testing?
Going into Australia, you would've been correct. This is why most people reserved judgement before the Aussie GP. However, after doing many many laps, in race conditions and in qualifying, its safe to say the car is genuninely fast and reliable.
In fact, in its double decker diffuser configuration, the BrawnGP car will be one of the most tested cars on the track, bizzarrely (along with Toyota and Williams).
dont really belive the car has so much reserve speed myself or barrichello could have used it in aus when he changed his nose
For whatever reason, the car is consistently faster in the hands of Button. Barrichello, to me, seems a little erratic, so far this season. However, whenever Barrichello is allowed to run in clear air, he does make up ground. The safety cars are forcing the BrawnGP cars to bunch up and are making it look like the other cars aren't that far behind, when in fact they are.
Its quite possible that the team are running with conservative settings, as they know they have plenty in hand - so why bother taking the risk of running the car on the limit when it isnt necessary? The giveaway was when Button was required to make those very fast lap times, before refuelling, which wouldve been done by abusing the car a little and running a richer fuel mixture.
Its been a while since we've seen this level of advantage and by rights, the BrawnGP should be qualifying and finishing races 1-2, providing the drivers keep their heads and dont do anything too silly. I'm not sure how long this advantage will last though.