Mark McGrath of AGLX has just done a really deep — 1 hr 40 min — dive into the heart of John Boyd’s OODA Loop:

Mark brings a unique set of qualifications:

• He’s a former US Marine
• He has spent years working with the OODA loop in his own businesses
• He also researched Boyd’s original notes at the Boyd Collection in the Marine Corps University Library in Quantico, VA.

This last part is important because the “loop” didn’t spring fully formed from Boyd’s brow like some modern day avatar of Athena. Boyd first used the term as part of the expression “operating inside the OODA loop” at least as early as the mid-1970s. But he never wrote down what it actually was. As recently as 1989, he was still describing it as a linear observe-then-orient-then-decide-then-act process, which would make further elaboration superfluous.

But in the early 1990s, when he was working on his last briefing, The Essence of Winning and Losing, he needed a sketch of the OODA loop. As he started fitting the pieces of that presentation together, he realized that the simple circle wasn’t going to do the job. After many, many, MANY iterations (I was involved with a few of them), he settled on the version that appears in that presentation. It is this collection of iterations, and many other hand-written sketches riddled with arrows and acronyms (some of which have yet to be deciphered), that Mark studied.

It’s a long podcast, so I’d recommend you take it a little at a time.