Fuel is one factor, power-mode the other. I think what many people had been suspecting, is that the C5 runs were probably done with a lower power-mode (with less fuel) compared to other slower runs where an evidently higher power-mode was used (although with more fuel and also a different tire). This masks the true pace somewhat.
Even so, as already said - I think the teams have a very good idea on where everyone stands, since they have way more information and tools to analyze the performance of their competitors and also get a closer approximation on power used. In the end, it's not a 100%, but probably much closer than all the calculations being thrown around here to make sense of the times.
Other factors include;
- the track temperatures at these tests were rather low
- these cars are still work in progress
- by the time they will actually race here, the cars will have gone through multiple updates and a much better understanding on how to set them up
- Melbourne and the first couple of races are very different tracks with different characteristics, different demands to the car and driver.
- Therefore; being fast on one track will not equal being fast on an entire different track.
- Qualifying/one-lap-pace is yet another thing entirely with the special maximum power modes that may compensate one flaw or another. Extracting the pace from the tires is also another thing too.
Not for nothing, Rosberg's Championship is the only thing that lends credibility to Hamilton's recent success. Otherwise, he'd just be the guy who's had the best car. — bhall II