One of the best articles about project management and software development Project management: A surefire way to kill your software product.
As a software developer I have to agree with almost everything stated there and I can confirm most of it as true. You cannot treat creative people as resources and think that inspiration and creative work can be normed and timed as in the case of an assembly line product.
A lot of people will disagree and say that their method is better that the article tackles only the wrong project management.
My advice: try to apply the your “project management method” to writing a book or to painting. If is it failing than it will fail also for software development.