ImpactPlayr....Ok the whole castor thing is a tricky subject. One thing that I have noticed on the Schumacher cars is with the large amount of castor that they have stock IE:6 to 12 deg when the wheels turn and the suspension is compressed like in a corrner there is about a 2 deg camber gain depending on the pos. of the upper arm and ball stud. Ok so normaly more castor will help with mid corner and exit but with this car you get increased camber gain which will lead to loss of traction in the middle and exit of the corner. I have tried running rear arms in the front and shaved a little off the back side of the front upper suspension mount to take out more castor. Now I can run 0deg castor and up to 12deg of castor. I like the car best with 2 deg castor and 2 deg kick up in the front which is a total of 4 deg of castor. But the way the suspension on our car is designed we get reactive castor with kickup in the front, so this means that the castor will increase as the suspension is compressed.
So what you said about with less castor you feel the car has more exit steering is correct. Because with the lesser deg of castor the camber gain is less which means more grip through the start and exit of the corner.
The way I run my car with so little castor and kick up the car turns in very well and changes direction even better. Now it does not get half way through the corner like it did and it just lack the grip needed to complete the corner.
One thing that I noticed that lead me to what i did was that I was always going through more front tires(rubber) then rear tires. Meaning they were wearing far faster then the rears and they were the same compound and same inserts.