This came up in another forum and I put together a spreadsheet based on the picture above. Using the dimensions indicated with a 3250 pound car (250 pound rear axle assembly), I calculated the moment (torque) about the front tire patch when the car is accelerating at 2 g's. I did this 3 ways: I used the force resultant at IC location A, the force resultant at IC location B, and the upper and lower link forces acting at their location points on the chassis. In all cases, the moment ends up exactly the same.
In other words, so long as the IC falls on the same constant percent antisquat line, the car can't tell the difference.
Since it's a spreadsheet, it's very easy to try other combinations. So, I pushed point A along that same percent antisquat line until it was about a quarter mile ahead of the car. Again, the moment comes out exactly the same!