Now, I do remember some of the elves at ERA telling me that rear toe-in is dialed in to help
braking, or rather control of the car while braking, but I have never heard of one of our cars accelerating and creating toe-out, whether it's Jag based, BMW based, or Fred Flintstone's feet-driven car. Now, I suppose it could happen, I've just not heard of it, especially if you have squishy suspension components.