Situational awareness is further lauded by elite military units, police trainers, criminals, intelligence analysts, and human factors researchers. In other words, people who have to make very important-- often life-or-death-- decisions based on limited information consider situational awareness a critical skill.

Note that most of those people operate in very time-sensitive environments. Yes, perceptual efficiency matters a lot with limited information.

In general, I agree that SA is useful, though I wouldn't quite call it the zeroth skillset. For the sequence, are you intending a description of what being SA means, or are you trying to prescribe a training regimen for SA? If so, remember to build small skills in the right order.