I get it and I don't agree with it but I am amazed how the drivers will obey it and not be all - i don't know - pissy about it after.
I believe the same thing happen between Button and Hamilton last week in China although Hamilton did not have the tires to get past Button anyway. They needed Hamilton to save the car and not take a chance of crashing due to the left (I believe) tire being completely bald and it raining.
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if you can only race me in a straight line then whats the point 
...91 SMF SCCA
http://www.flickr.com/photos/8341770@N07/5601083432/http://www.flickr.com/photos/8341770@N07/5601083432/ by http://www.flickr.com/people/8341770@N07/, on Flickr
I see people out there spending money on the car to improve it … If you spend half that effort just working on your driving skills, making you and the car work together as a team, then you’ll go faster – period. To make the car go a second faster on the track takes a lot more energy and money than making yourself drive it one second faster.
– the late Tom Thrash SCCA Solo E Production