The author's right in that this is truly a beginner's guide as it neglects to mention that optimizing TDS and extraction is a process that is not only contingen

The author's right in that this is truly a beginner's guide as it neglects to mention that optimizing TDS and extraction is a process that is not only contingent on the brewing method and equipment, but also the coffee being brewed. You're going to be doing this for every bag you brew. It doesn't stop. The more advanced guide will have you dialing in brew temp, preheating, pour schedule, recipe, water treatment &c. It really doesn't stop.