Mitigate does not mean eliminate. Which means there's still a possibility. Exactly as with the transmission fluid change.

Anyway I see no further point in discussing this with you if you're going to engage in ad homs. You have your opinion and I have mine. Until you, or someone else, can show supporting data for your claim I will continue to view this as nothing more than an urban legend.

Urban legend or not, there is certainly a very real possibility that BMW could deny you warranty repair on a transmission you opened when they told you not to. Have a go at your nav system and when it craps out see what they say. It only costs half as much as a transmission anyway.

Does that mean I am at risk of having my warranty denied because I change my engine oil more often than they recommend?

Honestly I don't know, but it's certainly something to think about.

On what basis would the denial be based?

I don't understand your question?

What would be the reason for BMW to deny a warranty claim on the transmission?

That it was opened when it wasn't supposed to be. (Seems pretty obvious)

If it's not supposed to be "opened" then why would BMW recommend it be "opened" at 100K miles?

Data belongs to the owner of the vehicle and/or the shop, not me. As an aside, I see little benefit in providing you data because you have repeatedly twisted the arguments to suit your own purposes.

And no, I never suggested that changing the transmission is likely to result in a transmission failure. I suggested that it is more likely to do so than it is to provide a benefit. Please review the above posts.;)

I am very happy for him. I guess that must be a very large sample size. I bow to his expertise, and your unwavering faith in him.

That is simply nonsense. When discussing lifetime fluids, please confine your examples to sealed systems with no outside sources of contamination. I suggested a shock absorber, but James didn't like that one. The issue isn't whether it gets dirty and breaks down; the issue is whether it does so before the transmission fails of other unrelated causes. Why is transmission fluid different than other fluids? Already explained it, sorry it wasn't in a form that was comprehensible.

You seem to think this is a BMW issue. Sorry, it isn't.

No, both are obviously possible, but as I already explained above, those particular examples were already discounted. They aren't a causal factor in the examples I am referring to. You are simply bringing up non-related points to confuse the issue. You need to come up with something new here.

I gave you the root cause, you just choose to believe your mechanic over others here. But since we don't know who he is, and he isn't here, I guess we will just have to take his opinion as fact.