I think if an AI developed completely new fields of thought or science.

But given our current relationship even if it did I can't foresee a point where it couldn't walk us through the necessary steps or supply the pros/cons for whatever problem is being addressed.

2 issues - trying to understand how it came to its conclusion because I feel true AI has got to be non-human intelligence. Or a something catastrophic happens and we as a species are back in the stone age. Imagine today's AI trying to converse with a cave man (yes, one without modern languages even).