The primary thing when you take a sword in your hands is your intention to cut the enemy, whatever the means. Whenever you parry, hit, spring, strike or touch the enemy’s cutting sword, you must cut the enemy in the same movement. It is essential to attain this. If you think only of hitting, springing, striking or touching the enemy, you will not be able actually to cut him.
The McNamara fallacy, named for Robert McNamara, the US Secretary of Defense from 1961 to 1968, involves making a decision based solely on quantitative observations (or metrics) and ignoring all others. The reason given is often that these other observations cannot be proven.
The fallacy refers to McNamara's belief as to what led the United States to defeat in the Vietnam War—specifically, his quantification of success in the war (e.g., in terms of enemy body count), ignoring other variables.
Design has very little to do with what tools or methodologies you use, or what your job title is, or what you have a degree in, or even anything like “creativity”; design is about your relationship to constraints. Rather: to what extent are you defining constraints rather than just obeying them? Design is about taking a universe of possibilities and converging onto exactly one outcome. Being handed a set of constraints which you treat like immutable laws of physics (because many of them are) and solving within that envelope is what engineering is. To wit: what most designers are doing most of the time is actually a form of engineering, and engineers are always doing at least some design.
This is because genuine design—the power to define constraints—is a privileged political position within an organization, and not everybody can occupy it. In other words, the “seat at the table” comes first. Design is Steve Jobs infamously dropping an iPod prototype into his fish tank, pointing at the bubbles coming out and yelling at his staff to make it thinner. It doesn’t matter what your title is; Jobs is the designer in that scenario.