I believe they are talking about a crease, dent or knick in the phosphor bronze bushings at the pivot. Probably relating to slow deployment.
I am not sure if this is exactly the case but i recently bought a blue tenacious which was a little difficult to deploy. At first i thought it was just a strong detent, but on closer look, i found it was stiff right past the detent, the blade swung freely in the middle then slows right before the lock-up. After taking the knife apart i found the culprit was a pocket clip screw that was just a tad too long and it went through the liner and knicked the very edge of the washer so there was a dent and a micron's length of screw in the way impeding the action. All it took to remedy the situation was moving the clip to "tip up" position, which effectively removed the offending screw from the pivot area the washer is soft so it smoothed itself out after a few open and closes.
