I have heard it said that if you truly prepare for a genuine full on mad max scenario all the other scenarios are covered by default. I used to say that wasn't quite true. Now I would clarify by saying that it covers you for a lot (versus all) other scenarios.
Obviously if you are prepared for a genuine end of the world event then a power outage or even a Katrina like mid length regional disaster is just a practice drill. Having serious depth in food you normally eat will let you wait till sales to resupply and thus get more food for less money. If you have 15+ mags per gun, cases and cases of ammo as well as plenty of spare parts you are well positioned for any sort of gun ban.
However it is also worth noting what the TEOTWAWKI plan doesn't cover.
It completely ignores all sorts of highly likely financial/ unemployment/ slow slide issues. That Cold War mentality where the only option is that everything will go just fine until the world ends misses this one. You need to be concerned about your overall debt as well as savings for a rainy day. Can you afford your super spiffy retreat if you lose that high paying job? Even if your 'retreat' is paid off it is only yours so long as you can pay the property taxes.
Also I have a concern that this sort of planning can lead one not to worry about the progressively more violent world we are living in because you'll just carry a rifle everywhere if TEOTWAWKI happens. That sort of mentality isn't realistic. My real concern with this bionary approach is that it heavily weights things like owning rifles and stashing sand bags n barbed wire against more practical concerns like concealed carrying a pistol whenever possible and other more realistic home/ personal defense stuff. You need to be worried a lot more about 2-3 armed criminals who are probably on drugs breaking into your place tonight a lot more than EU/ Russian/ Mexican soldiers enforcing world government upon you.
I think that if you keep a solid financial footing and put plenty of effort/ energy into preparing to defend yourself today then there is nothing wrong with the majority of your energy going toward the kind of worst case scenario deserving of a fiction novel.