Just when the teams were starting to get to grips with the 2012 tyre challenge, the use of the Pirelli supersoft will throw a new unknown into the mix for Monaco — which is why practice could make perfect this weekend.
This season has been all about tyre control so far, and with different conditions suiting different teams at each event that has resulted in five different winners from five different races. A sixth this weekend would be unprecedented for Formula One.
Each grand prix so far has used a combination of either soft and hard or soft and medium tyres, but this weekend the supersoft will be rolled out for the first time, as the Monaco circuit has much lower levels of grip due to the low speeds that create less aerodynamic grip.
The new tyre construction for this year is much squarer to the design used last year, creating a wider contact patch and a more consistent use across the tyre life. But the new range of tyres also appears to be far more temperature sensitive than in the past.
That will mean Monaco's fickle weather, and the constantly changing track conditions (due to it being a public road opened each night) will add further unpredictability into the mix and the arrival of the so far unused supersoft makes things more complicated.
Unlike the other tyres in the Pirelli range this year, the supersoft tyres use exactly the same compound as they did last year, but the squarer construction design is likely to mean they operate quite differently to their predecessors.
The supersoft has an extremely quick warm-up time and once up to temperature its super-grippy material delivers very good traction and enables much higher cornering forces. It will, however, degrade more quickly than the soft, which is the other option this weekend.
But Monaco is good for tyre wear. The track surface is the least abrasive of the year and this means the tyres can last long distances — in fact Pirelli predict the soft tyres could last for 50 laps or more.
To secure a place at the very front of the grid, however, the supersoft will be essential (last year everyone in the top 10 apart from Lewis Hamilton, in ninth, used them) — and with the race lasting for 78 laps that makes for some very marginal calculations on strategy.
Last year, the front-runners managed to get around 16-18 laps out of their first set of super-soft tyres (Mercedes a little less) but Kamui Kobayashi, in the Sauber, and Adrian Sutil, in the Force India, managed more than 30 laps.
The teams now know how to manage the new soft tyres to make them last, and if Pirelli's 50 laps is realistic then the supersoft will need to last 28 to add up to full distance on a one-stop strategy.
Last year, Vettel played that tactic but almost came unstuck because he only managed 16 laps on his supersofts and was losing grip on his softs before a red flag situation stopped the race. Had he not been able to then change his 52-lap old softs for a new set, he could well have lost his lead to the three-stopping Jenson Button.
The supersofts went away far quicker than expected last year - which means understanding what they are capable of this season will be crucial for deciding on whether a risky one-stopper is feasible or whether a safer two-stopper is the way to go. A three-stopper is a bigger gamble and would only be feasible if played cleverly, making the most of a clear track.
And that is why Thursday practice, when teams are trying to quickly understand how best to care for those tyres, and how long they can expect them to last, will be the most crucial part of the weekend.