This is not a model with the insert. The titanium lockbar is softer than the the steel blade, so naturally over a long time of use, the titanium will wear away at the point of contact against the steel. A lock bar insert is a piece of steel that's bolted to the titanium lockbar at the point of contact so that it's steel on steel contact, preventing premature wear.
Clear giveaway is a screw at the end of the lockbar. Yours doesn't have it, it just means that this an earlier model is all.