Studies have found that planning will reduce project budgets by an average of 20% and duration by almost 40%.
Which studies? “Perceptions of Representatives Concerning Project Success and Pre-Project Planning Effort” from 1994. That's around the time of the forst Chaos Report which hilighted the critical rates of failure and mediocrity that IT projects were achiveing.
If you are a fan of a little less planning and a lot more action you might like to take a moment to read this article. I am interested in readers comments.