I read those other threads and I've been having a similar problem with my dealer!!! I already got the updated throttle body and software installed/replaced on the tranny about a year ago. However, there is still some intermittent slippage present, especially when the car upshifts to 3rd at about 40-45 mph.
I made this aware to my dealer and they said the exact same thing: "Well, we didn't find any codes so there isn't anything wrong"
I stressed to them that since the warranty will almost be up, I don't want to be stuck with the bill when the tranny does go!!
They told me that since the problem is documented and has been for the past year that I shouldn't need to worry about it. . . I've been a customer with the local dealer here for 20 years and this is the first time they've reacted like this. . .