In board toe in in the rear has a geometrical function similar to anti squat but without the reduction in rear traction entering corners that happens with anti squat.
In board toe out in the front has a geometrical function similar to anti dive but without the reduction in front traction entering corners that happens with anti dive.
Out board toe in seems to give the stability you want from to in but also seems to allow the car to have more corner speed due to increased rear traction. Those of you who were around when the Yok MR-4TC came out remember that it had 0 deg inboard toe in the rear and 1 deg of toe in at the rear hubs. This car was awesome when it came out and its descendants the MR-4Pro and Worlds cars were even better with 2 deg outboard toe.
Losi came out with the XXXS and Schumacher came out with the Mission and a year later the Mi2. All of these cars allow you to adjust inboard toe out in the front (either 0 to 2 deg) and inboard or outboard toe in in the rear (XXXS and Mission 0 or 2 deg, Mi2 1.5 or 3 deg). Out board toe is adjusted with optional rear hub carriers in .5 deg increments.
FYI...this is why you see AE factory drivers with XXXS rear hubs on their cars at certain tracks.