A project that I've come across is 10 weeks into its expected 57 week duration. Its software architecture has been worked on for over 15 months prior to the commencement of the project. The key to a significant part of the project is a new data model that is planned to remove the problems associated with the existing ram shackled system. The new model has been worked on for 12 months. It is complex but uses industry standards and would make additional enhancements and inter-connectivity easier.
So imagine the surprise when the project leadership announced that it was going to think "tactically" rather than "strategically" and would therefore reluctantly scrap the new model. In its place we would create a simpler model from scratch within four weeks and the project would still be able to make its schedule and provide the level of functionality required. (Enquiries are on going as to the medication that they are using.)
As a rule when managers decided to think "tactically" they are saying that they have realized that they cannot make the project schedule they originally planned. This is usually because they underestimated the work involved, or in many cases didn't carry out any detailed planning work at all. Ball park estimates allied with over confidence are the usual culprits.
So if as a project manager you come across a project with a complex architecture and an aggressive time line be prepared to move into "tactical" mode sooner rather than later. Middle managers love to talk strategy but really they are tacticians at heart. Much happier with duct tape than with detailed drawings.