This classical iterative method, while powerful, does have a shortfall: Planning the correct content for each of the iterations is more of an art than a science.
此经典的迭代方法，虽然有力，但有一个欠缺：为每次迭代计划正确的内容更像是艺术而不是科学。
2
This method of top-down planning can be helpful early on.
在早期这种拉下式计划可以十分有用。
3
Whatever the planningmethod or the form of the plan, unlearning will very likely be needed to effectively use that plan.