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.
Another great dissertation from Mark Brown of Game Maker’s Toolkit: The Games that Designed Themselves. It’s the radical idea that designers should ignore their preconceived notions and look to the game itself to find out where the development should lead. How does something design itself? Well… the answer is: Prototypes.
A lot of great indie game masterpieces are the result of experimentation and early gameplay demos that changed the course of game’s development. As Brown points out, there’s a whole history of groundbreaking games that were developed “almost by accident” where bugs and glitches were turned into features.