i think maybe we could say that plan a didnt go according to plan, so they switched to plan b. is that a nice moderate compromise?
That's where risk assessments come into play. What are the risks associated with this operation, what is the severity of those risks, and how can they be mitigated. You're correct, sir - planners develop courses of action that provide the best chance of success with the least amount of risk. Sometimes other risks are identified during the wargame and rehearsals, but those are risks that can be mitigated without changing the overall plan. If the course of action has to completely change, you'll probably be looking for a new planner. (Geez, I sound like I've already been given the field grade lobotomy).