I remember reading in here that the little clear plastic tabs that come with the Adventure panniers are intended to tighten the locks somehow. Is that true? If not, what are those little tabs for? I have one mounting bracket/mechanism that's a bit loose, even when locked down (the latch isn't tight as it should be IMHO). I've been inserting bits and pieces of this & that to tighten that mechanism, but I think (remember?) that somehow that's what the tabs are for. True?