The subjective/listening component of equipment valuation is 100% necessary. Use of measurements only is limited to what it is that is measured. Since there are no "scientific" measurements for many sonic/music factors, measurements are only a starting point in evaluation.
To those of us who vehemently believe that cables can determine sound quality of a system as does a speaker, beyond their use as "tone controls," there are no scientific measurements which delineate why they sound a certain way. They are also system dependent. Quality of manufacture is perhaps, one of the strongest measurable components of a cable. I am a believer yet I cannot "prove" why my cabling sounds so good in my system. I've tried my cables in multiple systems, sometimes they are just as great (especially on more modern and high end systems) and sometimes they don't perform as well as expected (on friends mid-fi but good equipment).
Speakers are much easier to scientifically measure than cabling at this point.