Here's my take:
With the PCT method, if a bear does happen to get the bright idea to gnaw, pull, or somehow mess with your rope, it can only pull your bag higher into the tree or gnaw off a slack piece of cord not essential to the hang.
If you anchor one end to a log, tree trunk, etc., then IF a bear finds that end and messes with it, you're more likely to lose your food. What's the potential? Who knows. But if it did happen, you'd likely lose your food.
But I doubt a bear is going for your rope first. Most importantly, get your bag high off the ground, FAR from the trunk of the tree, and away from any other trees or branches or anything that a bear could climb. From what I understand, most hangs are not defeated by bears manipulating ropes, but by people underestimating what they can climb and what insane lengths they'll go to to snag a bag.