On topic question. Is one of the reasons for toe to impart some side force on the wheel bearings in order to take the slop out of the ball bearings? Ball bearing adjustment calls for backing off the spindle nut from tight to just enough slack in order to allow for inserting the cotter pin to keep the nut from coming off since it isn't tight to the inner bearing race once properly adjusted.
I am envisioning a properly adjusted ball bearing without any toe is, or not enough toe in wobbling around and causing vibration.
I have heard of modern vehicles with zero toe in, but they have roller bearings which are installed with a specific amount of residual preload which takes away all of the slack, thus no vibration.
