Alex, Looks like you are getting the vehicle tracking off the table and out where the consumer can benefit from your findings. I hope this becomes a long lasting project and brings many more folks to the forums, not just with complaints or tracking requests but all sorts of info good or bad ( hopefully not much of the latter) and add to GM Authority’s shine.
I am loving the new Denali although I have yet to make a trip over thirty or forty mile, the difference in performance is very noticeable but gas mileage has not approached the 2015 quite yet maybe when she has a couple of thousand miles on her it will improve.
As far as the cylinders being shut down when not needed, I cannot tell if this is happening or not the engine runs so smooth.
Just thought I would leave an update from one who had such difficulty finding a source for tracking a build.