On a race trans. things are done to get the elements to apply more aggressively, i.e. eliminate the function of accumulators which act as a cushion for the shift, crank up the pressure, use more aggressive friction materials, etc.. Applying frictions, starting and stopping elements quickly behind big power at WOT is much different than a smooth, unfelt shift at light throttle on the street.

Also the use of fluids that are not as slippery as modern fluids which are designed to make the application of lock up converters and frictions elements nice and smooth to satisfy the public.

I tried some Amsoil Synthetic street fluid once. The high gear plates came out black streaked from heat, obvious slipping on application. Never had it before, never had it after I went back to Type F. Good fluid. Not the right application. They do a synthetic racing Type F modeled after fluids used in transmissions in heavy equipment that need to shift while pulling heavy loads.

On topic, ATF shelves are empty at local auto parts, and it has been expensive for awhile. What does show up is gone in less than a day. Heater and fuel hose is also scarce. Next month it will be something else. This is the new normal.

The reported cause is a shortage of some additives.

And the Mag 1 brand of oils is cheap stuff kept for oil changes at shops who want the cheapest crap possible. Not even sold to the public. I have a little inside knowledge of what's going on in the local Advance stores.