it seems that way until the AI makes a mistake that even inexperienced players would be able to spot & avoid using traditional principles
Everyone makes "what was I thinking?" mistakes, and we should not conclude, from that, a lack of relevant understanding.
everyone makes mistakes, but not everyone makes the same mistakes. depending on their mistake, players very much can and do conclude a lack of relevant understanding. this conclusion is an integral part of the learning process.
Human players make blunders as well.
right, which is why humans do not claim to "grasp the significance" of their moves.