I consider it a very interesting thread where someone went looking for proof of shadow mode and couldn't find it. Maybe his conclusion is a little extreme, and I guess people thought I was trying to derail a Tesla thread with FUD when really I was trying to share an interesting piece and someone else's better-informed opinion (which is why I worded it the way I did). I sort of consider it similar to saying "expert A believes that..." but I guess I communicated that poorly.
For what it's worth, I'm glad people are actually looking at the source and critiquing it.
This seems to be assuming that it's something that exists entirely within the car, whereas the more sensible implementation is that the car uploads the sensor data and driver choices to a server in a datacenter somewhere and "shadow mode" happens there by running the autopilot code against the data.
That way you can continue to use the data even with newer or experimental versions of the autopilot code that didn't exist when some of the data was collected, compare different versions to see which ones do better and when, etc.