I have always assumed that the locking mechanism is only as strong as its weakest area. Consequently, I don't understand how a frame-lock could be stronger than a liner-lock. At least on my two Kershaw frame-lock folders, the strip of frame that engages to lock the blade has a thinned section. Obviously, the thinned section is so the metal can be flexed using a reasonable amount of side pressure, to disengage the lock. If the frame-lock were entirely the same thickness, and not thinned in one area, you wouldn�t be able to close the blade. But the thinned area is the same thickness as most of the liners on my other liner-lock folders.
So, why is the frame-lock inherently better (or stronger) than liner-locks?