One of the causes for unexpected AI behaviour relative to the player's car is a bug in the regular statements for feelers in the General section of the hdv file.
From the BMW/Sauber
...
FeelerFrontLeft=( 0.900,0.394,-1.950) // Front-left corner collision feeler
FeelerFrontRight=(-0.900,0.394,-1.950) // Front-right corner collision feeler
FeelerRearLeft=( 0.900,0.394,2.260) // Rear-left corner collision feeler
FeelerRearRight=(-0.900,0.394,2.260) // Rear-right corner collision feeler
FeelerFront=(0.0,0.384,-2.090) // Front side collision feeler
FeelerRear=( 0.0,0.384, 2.420) // Rear side collision feeler
FeelerRight=(-0.850,0.384,0.000) // Right side collision feeler
FeelerLeft=( 0.850,0.384,0.000) // Left side collision feeler
FeelerTopFrontLeft=(-0.100,1.010,0.720) // Top front-left collision feeler
FeelerTopFrontRight=(0.100,1.010,0.720) // Top front-right collision feeler
FeelerTopRearLeft=(-0.500,0.850,2.500) // Top rear-left collision feeler
FeelerTopRearRight=(0.500,0.850,2.500) // Top rear-right collision feeler
FeelerBottom=(0.000,0.080,-0.05) // Bottom feeler
...
If you look at the FeelerTop... values, (last 4 lines), the values for the first parameter, the location of the feeler in the X direction, is actually on the wrong side of the car. So FeelerTopFrontLeft is on the right hand side of the car and the ...FrontRight is on the left hand side of the car. This seems to confuse the AI - or at least fixing those lines seems to make them behave more rationally.