Ineffectiveness of Time Management Training

In the HBR:   " ... The problem’s not just that we’re getting distracted from work; it’s that we’re getting distracted from important work by other work. How many times have you sat down to do more thoughtful, in-depth tasks, only to be lured away by incoming emails from clients or colleagues? Knowledge workers are so overwhelmed by incoming information, they spend much of their time “playing defense,” operating without a clear picture of their total responsibilities.  ,,, "