.... For faster acceleration when in D,
you can get the transmission to
automatically downshift by pushing
the accelerator pedal to the floor.
The transmission will shift down one,
two or three gears, depending on
your speed.

I encounter something enlightening recently. I discovered an explanation to a mystery that I have lived with for years. During hard downshifts as I aggressively go wot at around 60 mph, my trans would get confused and stumble over itself. The car would not be pulling during this brief period of confusion. This would happen very seldom, about once every month or two months. I had just learned to live with it. But, I have always wondered what was going on with the trans. I would just think "Damn stupid computer".

I now know the cause. The first day after my first change, I was fortunate enough to have this situation occur. Here is what was happening with my previous Mobil 1 fluid.

As the trans performed an aggressive wot downshift at 60mph, the trans would drop into 2nd gear. But, the PCM would decide to shift into third gear BEFORE the trans actually completed the downshift into 2nd. So, this created an illusion of a stumble as the trans was almost dropped into 2nd and then shifted into 3rd... all happening as one continuous event. Messy.

Now, with the racing fluid allowing the shifts to occur quicker, this same event produces an awesome exhibition of shifting performance. The PCM downshifted and grabbed second and immediately shifted into third.

The difference here is that the car was pulling the whole time. And, the shifts occurred so close together that my mind did not have time to comprehend what was happening until a few moments later. Instead of a convoluted mess of the two shifts stepping on each other, producing a moment of confusion.... now I can perceive two distinct separate shifts occurring extremely quickly.