What's up with the kydex sheaths? All my factory ones seem quite tight; should I loosen the screws or does kydex tend to "break in" after a while. I should probably take a few minutes to read the paperwork that came with the sheaths -- it might explain that. Instead, I just tossed them into my "I'll deal with that later" pile. This thread reminded me that I still need to do something about them.