I finally voted for Button, on reflection he has been the cleanest and most decisive over the years. Also to balance out the poll, as its very 1 sided

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I must say I am surprised by the number of people who consider Button the best overtaker in the business. He made a lot of overtakes look easy last year, and has of course made many good overtakes in his career, but is making overtakes look easy and clean, the primary criteria for deciding upon who is the best overtaker?
Its hard to say because I think the thread title is somewhat ambiguous, given that 'best' can be interpreted differently. For me, I would deem the 'best' overtaker as the driver who: 'is most successful at gaining track position, the driver who if behind - is the driver most likely to perform an overtake and make it stick, preferably in as short as time as possible.'
I had a look for some information on on track overtaking for this season and over the last few years.
I found this on 'clip the apex' forum.
http://www.cliptheapex.com/forum/viewtopic.php?p=20025#p20025
Now the numbers vary due to the criteria decided as a legitimate overtake, and is of course susceptible to subjectivity on some instances.
I also concede that the most overtakes does not automatically = 'best' overtaker status. That said, I would expect someone who is considered the best overtaker F1, would have that reflected in somewhat in the statistics. For Button this is not the case.
A quick look at more 'long term drivers' yields a list of drivers who have a higher average overtakes per race since 2004.
Barrichello
Alonso
Hamilton
Schummacher
Kubica
Massa
Sutil
Glock
Now during 2007/8 Button had pretty rubbish cars, but Mark Webber who has a similar overtake average has had arguably worse cars. Sutil has a higher overtake average than Button despite having even worse cars.
Now stats are stats and can be read into too much, but are quite useful for indicating possible trends and patterns. This data certainly suggests that Button isn't a prolific overtaker, this reaffirms (to me at least) my suspicious that Button is often too conservative, rather than taking potential risks.
Coming back to my original definition of what
I think defines the 'best' overtaker - 'is the driver most likely to perform an overtake and make it stick, preferably in as short as time as possible', would I consider Button that driver? If it was an overtake that absolutely mattered, perhaps. Button is often makes that overtake when he really needs to. If it was just you're average racing situation? Probably not.
There are other drivers, who are not only able to make that move when it really matters, but are there time and time again making important passes. If I was a betting man I doubt I would be sticking my money on Button to make an overtake.
What's interesting is that Alonso's overtake average(while very reasonable) is still around the same as Barrichello, Glock, Sutil. I guess you could argue that for Alonso (and to a lesser extent - Button), that is hard to overtake anyone if you are on pole and lead the race from the start. This is perhaps why Hamilton's average overtake per race seems disproportionally high relative to the others, while Hamilton is obviously very fast in qualifying he has been (at least this year) starting from quite far back on the grid due to mistakes or team mistakes. etc. Also He has had far more than his fair share of 'drives from the back of the pack' for whatever reason.
Interlagos 2007, Fuji 2008, Nurburgring 2007, Monza 2008
All things considered, I don't think Button has an aggressive enough mentality to be considered the 'best' overtaker in F1, and by aggressive, I don't mean pushing other cars around and throwing your car into the corner first, I mean too conservative to really go for the overtake in the first place.
I've already stated in this thread, I consider both Alonso and Hamilton as the best overtakers, not only do they both posses an extremely high standard of technical ability when it comes to overtaking, they have the right mentality to take the opportunity when there is just the vaguest hint of success, and turn it into an overtaking move that works. Hamilton is particularly opportunistic, or as some would say - kamikaze.
All my humble opinion of course.
