This week in Valencia has always been the target for most of the F1 teams to have their new designs completed and ready to run, giving them the maximum track time over a total of four tests (15 days of running) before the season-opener in Bahrain in just over one month's time.
Early running is never a great indicator of things to come, and after this test, indeed even by the time the second test in Jerez ends on February 13, the true picture will be far from revealed despite wide reporting of lap times and paddock chat from the track.
Yet deep in the data, the teams will have learned a huge amount about where they are headed in 2011. So what will the teams be focusing on in Valencia?
The shakedown run is the first crucial indicator that everything fits into place as expected, and it is used for nothing more than that.
Ferrari has already given its new F150 machine two short private runs in Fiorano, with Fernando Alonso doing a shakedown after the car's launch and Felipe Massa doing an FIA-legal 60km filming run, in damp conditions, to ensure they were ready to hit the ground running in Spain.
For the other seven, which includes last year's front-running teams Red Bull, Mercedes and Renault, the Valencia test will not be the first time they have started up their cars but it will be the first time they have done all the running systems checks in action. For them, then, the first day will be about simple systems checks rather than pace, so Tuesday lap times will likely be fairly irrelevant.
Further to this, teams typically follow the initial shakedown test with longer run reliability checks, and Ferrari has already intimated that will be their plan for the early running of the F150.
The following two days, then, will likely be focused on reliability rather than performance, as if there are any major issues then it is important to get a handle on them quickly to give enough lead time to have new solutions ready before the season starts in Bahrain.
Most teams will have assessed their cars on rigs in the factory, but simulation and reality can be quite different. Elements such as internal temperatures generated by engine, exhaust, gearbox and even tyres are not testable in non-track conditions, and anything that is note quite right can take time to adjust.
As an example, the solution created by McLaren to mimic Red Bull's blown diffuser had teething problems, and it took them several days of practice running to establish the problems, create solutions and test them to finally reach a successful solution.
Aerodynamic proof of concept
The aerodynamic characteristics of the car are also important to check in these initial tests, as again sometimes the reality of on-track testing does not correspond to the numbers that were coming out when the model was being tested in the wind tunnel or on the CFD systems.
Although there are high-tech developments in wind tunnel technology these days, in most cases wind tunnels cannot consider the intricate full motion effects that occur as wheels steer, suspension moves and parts flex during a lap — and these can make a big difference.
Any problems in aerodynamics can be highlighted during reliability runs and they are often quickly discovered but rarely quickly solved.
Parts like the front chassis, nose, engine cover and sidepods have relatively long production lead times — so if there are any issues then the earlier they can be spotted and the parts re-designed, the quicker the team will be able to get back on track with new solutions.
Much has been said about the new tyres, and although the structure has been tested already in Abu Dhabi at the end of last year, the compounds have still been under development.
The grip created by those compounds will affect the forces going through the tyre's structure and therefore alter the dynamics of the tyre and how its form alters throughout a lap.
This can affect many things, including the stresses on components and the airflow over the car, so teams will be keen to quickly get to grips with what is happening — so much so that some may run 2010 models as well, to assess the difference.
Certainly McLaren, who will not have their new car until after the first test, will be making this the major focus of their Valencia test.
Radical rule interpretations
Finally, although some teams have hinted that they will be interpreting the regulations in a very aggressive way this season, it is unlikely this will be fully seen in the early tests, unless the radical design is integral to the overall car (as in the Renault design, it seems).
In the cases of front or rear wings and other easily added on parts, radical solutions may not appear until closer to Bahrain, when the teams that have created them will be confident their rivals will not have the time to produce copycat solutions before the opening race.
It is often the case that items such as front and rear wings can change significantly between the launch of the car and the opening pre-season tests and the first practice session of the season. Indeed, talking about the new F150, Ferrari's Aldo Costa admitted: "The aerodynamics is simplified and temporary for the first tests, waiting for the real aerodynamic development for the first race."
So while it will be exciting to see the new cars out on track, take the times they set with a pinch of salt.
These three days in Valencia are still crucial testing days, just not very important in terms of setting a pace. It will be the final two tests, in Barcelona between 18-21 February (which has a greater variety of corners) and Bahrain on 3-6 March, where more answers about F1 in 2011 will be revealed. So until then, don't place your bets...