Formula 1's delivery of thrilling grands prix in 2011 may owe much to the new rules introduced this year, but detailed mid-season analysis of exactly what has boosted overtaking has revealed that it is not DRS that has been the sole reason for more spectacular racing.
The sport's leading figures took a bold step this year in introducing a series of changes to spice up the action – with overtaking being a key area where improvements were sought.
Alongside the return of Pirelli, which arrived with an aggressive intention to make races better via their tire compound choice, F1 also embraced the return of KERS and the introduction of the radical adjustable rear wing. While the rules have been a step into the unknown, the initial impression is that DRS has been a huge success, with Nico Rosberg telling AUTOSPORT earlier this year it was probably the best idea in F1 history. On the other hand, some, like 1997 World Champion Jacques Villeneuve, have argued that the changes make F1 artificial and therefore a turn-off.
So, how successful have they really been? Statistics released by Mercedes-Benz ahead of the midway point of the season have now offered some insight into just what factors have made the biggest impact in improving the show.
In the first nine races of this season, there have been 623 overtaking moves in total – a figure which takes into account passes by the fastest cars on the slowest three teams, but discounts moves on the first lap or those due to damage.
Discounting the moves by the fastest teams on the slowest, DRS has accounted for 29 percent of passing maneuvers in 2011. DRS moves have outnumbered "normal" passes on four occasions: Shanghai, Istanbul, Barcelona and Valencia.
Significantly, DRS's impact has varied from circuit to circuit, and in direct correlation with its positioning on each circuit. At Monaco and Silverstone, where the DRS was on the short pit and Wellington straights, respectively, it accounted for just eight passes in total.
At Istanbul, a track notoriously difficult to pass on, the DRS zone was located on the long back straight on the run down to Turn 12 – and it consequently led to 50 passes, the most of any single circuit.
The figures therefore tend to suggest that while DRS has aided overtaking in general, it has not had an overbearing influence. Silverstone, for example, witnessed just six DRS moves but produced a fraught and ever-changing race right up until the checkered flag. Istanbul meanwhile produced 50 DRS-assisted overtakes, but was no more memorable.
Analysis of the new Pirelli rubber provides similar conclusions. While much has been vaunted about the importance of fresh rubber, on average 54 percent of overtaking has been done when the tire ages had a difference of less than five laps – DRS-assisted or not.
At high-wear circuits like Barcelona, the figure is slightly skewed as "old" tires – with more than five laps difference – accounted for 69 percent of maneuvers. In Montreal and Silverstone, however, tire wear – directly at least – had a much diminished impact.
The statistics therefore suggest that while DRS and the new Pirelli rubber may have contributed to overtaking, they have not become too important, or too decisive. Normal passes are not just still possible, but actually more frequent.
The data also suggests that each circuit's individual characteristics can have a heavy influence on the action. Turkey and China, with their long straights, produced a glut of overtaking, while the narrow confines of Monaco dented such ambitions.
At troublesome circuits like Valencia, yet to produce a truly gripping race, the new F1 initiatives have helped the show. But they have not artificially altered the game beyond recognition – Canada still produces great overtaking opportunities and great races, Valencia does not.
That variation is key to the sport's future, and suggests that – for now at least – the powers that be have got the new rules entirely correct.