We get plenty of emails in Microsoft. Without a system to manage them you are dead. Or better, your mind plays strange tricks on you making you think that you still have work to do. You need to convince your mind that you are done for the day and to stop bugging you, please.
Almost everyone has a system. Some are better than others. My current system is "Getting things done" and it does achieve its goal of freeing my mind (mostly) without imposing too much overhead. But I'm always looking for something better. That's why I checked out "Total Workday Control".
The title conjures in my mind all sort of scary images of control freaks going through their days trying to achieve optimization of every single action. In reality the book is just a light update of David Allen methodology. The most interesting thing I picked out is the differentiation between a Master Task List and a Daily List. The former contains projects or delayed tasks while the latter contains tasks (typically taken from the Master List) that you want to perform today. It also has a system of prioritizing such tasks and give good rules of thumbs on how many you should have on each list and so on.
My rule of thumb is that if I learn one useful thing by reading a book, then it is a fantastic book. This book qualifies. If you are currently using "Getting things done", this book constitutes a nice upgrade. If you aren't, I suggest you read David Allen first, as it gives you the reasons for the system, before you move to the more technical "Total Workday Control".