This is true for anybody and not just academics; but it is true for academics in the sense that most of what they do everyday involves research, writing, editing, revising, reading, etc. And the "intensity" that is often required in terms of concentration is very high for most of this work they have to do everyday. Academics read books and articles with jargon and technical terminology in their area of specialization; and this 'dense' content requires a proportional 'density of intensity' with respect to any task related to it, wether it be reading it, writing it, editing it, or researching it. So when an academic looks at their action list, there is not the same sort of proportionality with respect to high versus low levels of energy required to complete their tasks. David Allen's "time --> energy --> priority" comes into play here. Of course an academic only has so much time and so much energy to complete the tasks they need to get done every day, but part of what makes it so complicated is that when that caffeine buzz wears off at about 3pm in the afternoon and they really only have the energy for low-level tasks, they are staring at a list of actions that require a lot more energy to complete. GTD can't really fix this problem, but it does at least diagnose it. GTD can't circumvent the human limitations -- and the academic limitations -- of energy-level and time needed to complete any given task. The problem is that most academics just seem to have a lot more of them.