This was an interesting listen, it seems it's primarily concerned with accidentally breaching the 'secure area', which for anyone who doesn't know is all points beyond the check-in area of the airport. Check-in area is where items that must be declared aren't deemed to be a security risk for the sake of being staged for permissible transport. In other words, a designated area in which declared items can be prepared for legal transportation.
Any item that is required to be declared that is moved into the secure area is assumed to be a security risk and the product of hostile intent. So, an item that has to be declared before it can fly, can definitively NOT be allowed into OR through a checkpoint, AT ALL. In terms of security protocols, not an unreasonable assessment. That said, accidents and neglect and forgetfulness all happen to be part of the human condition, so it's not always appropriate to prosecute every offense on the basis of hostile intent.
My summary on this is cover your bases before you leave your primary residence. Verify that you've compartmentalized your luggage appropriately according to the legal requirements for checked baggage, declared baggage, and carry-on baggage. You try waltzing through the TSA checkpoint with a declared item, it's an invitation for scrutiny and prosecution. Put on the big boy pants, divvy the luggage up into what goes where, declare it appropriately AND immediately. Also, TSA Pre-Check is your friend if you're going to fly with guns ever. It tells TSA with a glance at your ticket that you voluntarily paid for and cleared a thorough Federal background check that stays current. TSA is going to swab your declared items no matter what, but if you declared your items and the TSA is routing it to the aircraft, you won't incur any unnecessary time penalties as a result of having to go along with your luggage to be checked.
That's my thoughts...