I was going to respond, but I can't keep up with your editing of your responses. What happened to the circular argument you posted about burden of proof? Did you see the flaw?

In the particular case under discussion, I think that the owner needs to confirm that the correct fluid was used, that the level was correct, that there were no leaks, and that the work was done properly. Then, I expect that during teardown a cause of failure will be found. If that failure relates to a hydraulic circuit that has debris in it, I think a reasonable hypothesis will be that the powerful detergents in the new transmission fluid acted as they are designed to do, and cleaned out the sediments, where they lodged in the small passages of the valve body. Cleaning out the valve body now may in fact restore the functioning of the transmission.

I don't think the example is meaningless, but for a reasonable conclusion to be drawn, I would expect something along the lines of the above. Is this the statistical proof based on a sample of 100,000 that you asked for? No, but it is how trained technicians work, and it is the best we have.

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2007 X3 3.0si, 6 MT, Premium, White

Retired:
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2003 X5 3.0 Steptronic, Premium, Titanium Silver
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