Order 66 just makes more sense and seemed more diabolical and chilling all along when you saw it as an implanted "switch," one that once flipped would turn easygoing, friendly Clones (at least to their Jedi commanders if not their enemies on the battlefield) into determined, brute killers. I understand the argument some make that "it's more interesting from a dramatic standpoint if the Clones receive Order 66 and then question and fight it," but that would be one incredibly unreliable and sloppy piece of programming to introduce into the Grand Army of the Republic. A protocol that you won't even activate for almost a decade and a half and when you do won't be followed by many Clones, who'll rebel and fight the instructions?
That wasn't what I was saying, though.
I'm fine with the act of a switch flipping and having them coldly take out their former friends and comrades without a second thought from a dramatic standpoint. My point was that that kind of dispassionate action is indicative of a greater level of programming than simply "follow all orders from the Republic leadership unconditionally."
One can follow orders while not liking it. Doing it coldly like sociopaths indicates that all feelings of loyalty and rapport with the Jedi were tossed aside the moment the switch was flipped too, because no one even hesitated or felt guilty. Which is why I was always a bit suspicious of the Kaminoans from the first time I saw all the prequels. That's all my point was. That, and the fact that this arc showed that their betrayal was even greater than I had previously suspected.