Strategy, Tactics and Heuristics for General Research: A Structuralist Approach, by Rob Tow, p.135 in "Design Research: Methods and Perspectives," Ed. Brenda Laurel, MIT Press, 2003

Heuristic - cognitive "general rules of thumb"

• This describes a set of rules developed to attempt to solve problems when a specific algorithm cannot be designed. For example, if the problem is "When do you eat food?", if you answer, "When I'm hungry" then you would have to eat immediately every single time you were hungry. Instead, we follow heuristics to determine when to eat by gauging our hunger level, the situation we are in, and our ability to get food. As you can imagine, heuristics are very important for solving artificial intelligence problems.
  at http://www.findanyisp.com/glossary/Heuristics.html
  
• GreenWIKI says Heuristics are Harmful (Which is also a heuristic.)
  http://greenlightwiki.com/heuristic/Heuristics_Considered_Harmful
  
• Compared and contrasted with the words "optimal," "specific," "algorithm," and "metaheuristic." http://www.worms.ms.unimelb.edu.au/digest/heuristics.html

After reading the material listed above, you may come to the conclusion that heuristics are simply "one's best guess" applied methodically

These three definitions, by military historian Liddell Hart, open Rob Tow's essay,

Grand Strategy - Single, overarching, high level end goal; supported by more than one strategy (ex. ruling the world, or just the market)

Strategy - Distinct patterns of action (ex. guerrilla warfare, genocide, targeting the teen market)

Tactic - Details of the day to day struggles (ex. infantry assaults, pop-song ring tones)

 

Rob Tow's article

"What to do next? And how to do it."

Rob Tow engages in design research. In this essay he differentiates between strategy and tactic, as driven by the goal of "economy of effort." Instead of "falling in love with a whizzy strategy, or mere tactic, and then dreaming up something grand to go with it," Rob Tow uses a structuralist approach to find the "void--the unpopulated area where nothing yet exists."

Structuralist Approach - "describing the essential qualities of an existing design space, technology or user experience and the imagining or inverting a small number of its specific qualities. In this way, it is akin to the deconstructionist creation of the "other" by knowing the "self."

"...a powerful analytic tool for design. We describe experiences and affordances, creating a cartesian multi-space [three dimensional grid] and note where existing things cluster. Then we not where the unpopulated loci are and describe their nature in terms of experiences ans affordances. Then we analyze the technology needed to support their existance and proceed to actual engineering."

An aside: "but sometimes there is no way to create the capability that can populate the void--we call this unobtanium."

Rob Tow goes on to describe several projects, and how his design research theory has been modified by the work he has done.