The author confused "constraint" which are rules or boundaries that define a situation or problem. She confused "constraint" With "strategy" which is a meta solution or algorithm to achieve a goal. A strategy doesn't have to be Google Maps giving you turn by turn directions. A better strategy is a set of rules or algorithm to guide you towards your goal; in all situations, situational awareness and common sense trumps any algorithm or strategy. It is like Google Maps telling you to drive straight while your eyes are telling you the bridge isn't there and driving straight will cause yourself to fall into a river.