Notably, even though the measurable criteria are "Hows", they are broad, generic and still very high level compared to "Hows" in the traditional sense. For example, ":minimizing the number of different fluids" is higher level than "no hypergols" which in turn is still higher level than "use EMAs for gimbaling which is a possible design.
Higher (lower numbers) criteria may include attributes of lower (higher numbers) criteria, as in this example. This has a tendency to make the list appear redundant when it is not. What really occurs is attaining higher criteria means sometimes attaining other lower level criteria automatically. As the criteria number increases, the expected potential returned improvement decreases. As a general rule of thumb, the Criteria 1 has twice the payback of Criteria 10 which has twice the payback of Criteria 20 and so on. Thus a technology that scores high marks for Criteria 3 has potentially twice the payback of a technology that scores high marks for four of the criteria above Criteria 25.
Further...
3.3 The Operability Criteria - Listed
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Edgar Zapata, NASA Kennedy Space Center
Shuttle Process Engineering Directorate, Fluid Systems Division