"In preparing for battle I have always found that plans are useless, but planning is indispensable" - Dwight D. Eisenhower
There is always a fear when embracing Agile that things will fall into chaos and that planning and strategy go out the window. I have been on projects that have run into these types of issues, and a big part of that stemmed from the team losing sight of the big picture goals and direction for the project. One thing that has been very helpful in preventing chaos and keeping things on track has been: release planning.