Discussions like that make me glad to be here in Oz where the people threat is much reduced in most areas.
In bayside Melbourne the real threats are much more flood (ww are only marginally above sea level) tempest, pandemic and then power, water gas cutouts. We lost gas for a someweeks a couple of years ago - hot showers became a premium and people died trying to connect bbq gas to hotwater heaters etc. Now most homes will proably have both gas and electric capability to some degree
In that context strategy #1 is wait it out - or to misquote the bushfire strategy (critical for those in rural areas) leave early or be prepared to stay and defend. Stay and "defend" means beign prepared for food and other essentials for 14 days and being prepared for the aftermath cleanup. The idea of taking my young family on clogged roads with only what we can carry on out backs at least 60km to a friend place or some temperary camp is singularly unappealing and something to avoid if possible. A good knife would not compensate for being in a shanty town with everyones bugs sniffles lack of hygiene, erratic food supply, possibly no one we know to trust and work with, etc. Obviously there are times this is unavoidable but I won't be joining a rush unless really necessary
I suggest looking at this from the Australian Red Cross - compiled from the red cross expereince in a number of disasters around the world.
http://www.redcross.org.au/ourservices_acrossaustralia_disasteremergencyservices_default.htm
Notice it alos features working with your neighbours that would be an important issues for us - particularly if we needed to provide some level of security and joint clean up in the short term
For long term survival preparedness the 7th day adventist manual looks pretty good - again it also empahsises working in groups