Until pretty recently, the gear a man carried in his pack and on his belt were normal "living" items; equipment he needed to live his day-to-day existance. "Survival" had no seperation from normal life.
It is (or was) assumed training and experiance permitted man to live and thrive without a wide array of gear. Much of what he needed was derived from nature. The natural man would be amazed to find ETS members agonizing if five blades were adequate, or do I really need a sixth. In addition, he was generally not interested in being "rescued".
Mears may also assume anyone who mastered the skills outlined in his book would be smart enough to figure out the basic equipment needs, based on season, terrain etc. You need to do the dirt time. Lets remember, ETS is too often aimed just toward the toys, not the skills required.

"There is nothing so frightening as ignorance in action."