Interesting wheel alignment

Rear total toe and it's vector direction(thrust angle) were adjusted on VW1302 Super Beetle yesterday by means of precise measurement with some special horizontal scaling tool equipped with LASER pointer.
Precise procedure brought a completely different driving taste on earth proving that the steering reaction is the most influenced by rear axle constructive axle geometry and wheel alignment. In another words, I might change the driving taste of any automobile in any way I want by adjusting of constructive axle geometry and wheel alignment adjustments.
As we know the running direction of an automobile is dictated by the rear alignment vector angle, so to speak thrust angle, this fact is easily imagined if we remember that a fork lift steers by means of rear wheel control. The error on thrust angel is adjusted by the driver in ordinal passenger's car. We must pay attention here on the point that the frontal axle is so designed as to be adjusted keeping forward automatically, this physical construction is called as self steer effect. The phenomena of this correction has an innate habit to reverse at the speed of 60 km/h, the steering habit changes into different direction.
Though I cannot explain why the clicking point should be at 60 km/h, the elements of caster, SAI, scrub, camber setting should have deepest relations with the phenomena. Thrust angle error is correct by the action of a driver as it is below 60 km, but above that speed too much self steer effect is exerted, so the adjusting direction on the steering wheel reverses. This truth and fact are not so common even among professional engineers. I would try to know how this reversing phenomena happens and to explain from an academic physical point of view.