Here's how we're defining "design" in the new FM 5-0 draft chapter 3:

"Planning consists of two separate, but closely related components: a conceptual component, represented by the cognitive application of design, and a detailed component, which introduces specificity through a formal planning process, such as the military decision making process. During planning, these components overlap—no clear delineation exists between them. As commanders conceptualize the operation, their vision guides the staff through design and into detailed planning. Like planning, design is continuous—it evolves with increased understanding and drives the operations process. It underpins the exercise of battle command, guiding the iterative and often cyclic application of understanding, visualizing, and describing."

"Design is a methodology for applying critical and creative thinking to understand, visualize, and describe complex problems and develop approaches to solve them. Critical thinking captures the reflective and continuous learning essential to design. Creative thinking involves thinking in new, innovative ways while capitalizing on imagination, insight, and novel ideas. Design is a way of organizing conceptual work within an organization to assist commanders in understanding, visualizing, and describing the operational environment and to develop approaches to solving complex, ill-structured problems. Design occurs throughout the operations process before and during detailed planning, through preparation, and during execution and assessment."