The GM tool has a mileage checker, too, and will alert the user if the car it is hooked to has an internal odometer reading that is less than what it had on record for that VIN at the last session. So far, it just gives a warning, but I suppose they could just as easily make it refuse to load a file... which could be interesting as many of the newer GM slushboxes have the TCM internal to the unit, so when they die the replacements need to be programmed (unlike a DSG, they come "empty" with no software at all).
You should see the new fiasco that FCA has... ROFL... what a trainwreck that is. Every time you start the program, you have to generate and load an access code, and you have exactly 31 seconds, or it locks you out. You get three attempts. If you do not get the code loaded after that, you get to call a 1-800 number and have to convince them to let you try again. Given the fact that the 31 seconds is barely enough, if there is a slow internet connection (on our end OR their end) that day, then....
And those cars have software updates weekly, for just about everything. It is nuts. I could spend all day every day just doing FCA software updates.