Well I guess the point i'm trying to get at is this. If you go on a job to say fix a dishwasher. You don't neccessarily use every tool in your bag to accomplish the task. In a Survival situation the job is to get out alive, and the survival kit is your tool kit. Do you need every "tool" in your survival kit to accomplish this? It seems clear to me that the answer to this question is sometimes you might but not always. When planning a survival kit you try to cover every possibility that might come up making sure to cover the most likely possibiliies first, but when the emergency actually occurs you may well have covered some possibilities that you don't actually face on that occasion. I submit that you don't actually put together a survival kit with the intention of using everything in it, although in some cases you might have to.