there is a common thread that I hear on these podcasts being mentioned by the “trainers”
Shooting from cover - unless you are using your gun safe as cover pretty well everything you are hiding behind in your house is concealment. In a recent police shooting the retreating officer was shot through his “cover” - the wall. Being taught that your house provides cover implies a certain amount of false security. Everyone is “taught” or sold on buy this, use that because of over penetration (outgoing defensive fire) to prevent accidental shooting of innocent bystander, than why the hell are they not being taught that this same over penetration exists on the incoming fire from the bad guy.
We have watched way to much Hollywood gunfights where bullets just spark off of inside walls or we can use the couch or upturned coffee table as an effective means of cover and protection from bullets.