A while back, I was inroduced to a different take on PDSA, the OODA Loop, Observe, Orient, Decide, Act. The genesis of the OODA Loop is found in the Korean War, codified by a USAF fighter pilot. In the business world: Observe - Gather your data, Orient - Determine how the situation fits within the organiztion ecosystem, Decide - Plot your actions, Act - Do it! But, as in a dogfight, these steps are all occuring as one ongoing feedback function. In any environment, for every action there is a reaction. Unfortunately, unlike physics there is no constraint as to magnitude or direction and, hence, may be quite unexpected. Using a continuous process of small, finite steps, with contiuous feedback appears to me to make the OODA Loop more efficient to reach the desired outcome, while minimizing the unforseen reactions.