My experience with a recently purchased small 31 in S45VN fits with your description, specifically, that the lock bar will flex (even though I called it "lock rock" in a previous post) so badly that it compares to some of the more outrageous videos on YouTube. For example:
I can place my knife on a flat surface, open and blade down.... While the knife rests on the handle scales facing blade down, I can place force on the back of the blade and see it bend all the way to the surface below.
This experience has been rather disheartening - I would have never imagined a CRK, which as a newer collector I have strived for, has less integrity than a gas station knife.