The techniques in 15.404-1(b)(2) are set out in order of preference. 15.404-1(b)(3) introduces this concept and says that the techniques other than (b)(2)(i) and (ii) may be used as required by the circumstances surrounding the procurement if, and only if, (i) and (ii) aren't available. So you can look at this step-by-step narrative as compliance with FAR 15.404-1(b)(3) requirements.