"Blending" is a time management concept for smoothly integrating two separate groups of tasks or parts of your life into one united field of productivity. An example might be blending your home life with you educational life by cutting out grocery coupons while listening to a recorded lecture. This sort of blending works well because no great concentration is needed for coupon recognition and cutting while the auditory concentration required for listening to the lecture is not impeded by coupon snipping as it might be impeded by reading Homer's Iliad. By doing these two tasks from separate parts of your life interests, you have blended disparate areas of productivity which resulted in greater productivity and well managed time. But what about other life areas? Do they blend as well?
Of course, a "diary" is a catalogue of routine entries made consistently over time to record past events, upcoming events or appointments, feelings, experiences, and various notations. You can see from the structure of the short article--which is divided into an Introduction followed by five entries beginning on "Thursday" and ending on "Wednesday," but omitting Saturday and Sunday, while closing with a Conclusion--that it records a catalogue of routine entries. These entries record Shellenbarger's experience with her experiment in time management blending.
"Mad" is an interesting word to include in the title as it has three applicable connotations each of which adds much, separately and collectively, to Shellenbarger's communication of her opinion of her experiment with blending.
The first connotation express a rapid frenzy of activity depicting someone who is never at rest. This is precisely the objective of the blending theory: avoid idle, wasted resting time during your work routine.
The second connotation expresses anger, as in someone who is displeased with a person or event, such as a failed experiment. This suggestion of anger fits Shellenbarger's experience precisely as she records that both her son and daughter were displeased with her lack of attention while ostensibly seeking their company.
The third connotation is expresses the idea of someone who has lost their reasoning power and their ability to operate in rational reality. In other words, it is what someone might feel after doing something they can't really justify or adequately explain to themselves. This is precisely how Shellenbarger might reasonably feel after her week of blending because (1) she hurt her childrren's feelings and disappointed them and because (2) she lost work productivity and broke work promises while also temporarily disabling he creative powers:
My jampacked week has produced not one fresh idea or novel insight. Only after family needs force me to take a complete break does my mind kick back into a creative mode.
Her title, then, can be paraphrased as "Record of a Foolish Experiment in Maddening Task Blending That Hurt Me More Than Helped Me." This suggests a fourth interpretation built upon a metaphor between Shellenbarger and a madly whirring food blender that is wildly blending up multiple ingredients into one glutinous puree like Shellenbarger did for week to her family and career for the sake of sorted mail, postcards and a neatened desk.