Is it fair to say about the aggressiveness and efficiency of a razor is ? Aggressiveness: its the parameters the manufacture has set in blade gap(predetermined or varying as like in a adjustable razor) and blade exposure(positive,neutral,negative) with guard(hybrid or dimpled or just smooth straight) and Cap(OC,normal or Scalloped) also weight (plastic, brass,stainless steel,aluminum..)all combined before a shave starts in it's static tightened blade loaded razor. As the shave starts Blade feel aggressiveness indicates, as it mows whiskers. Efficiency: With the set parameters of the razor by manufacture and blade loaded how well did it perform with good hand technique along with 1st & 2nd shave use with a new sharp blade by operator of the razor! = end results DFS or BBS. (Another way to bump up efficiency is to shower or hydrate skin & beard with warm wet towel, use a new Gillette silver blue blade with your favorite razor should give you even better results.)(edited Aug15/2018) This is my interpretation of aggression and efficiency of a razor, what is yours?