I argue that one has to unlearn undergraduate writing skills to learn a completely new skill set to survive.
Research suggests attrition rates of between 50% to 65% for PhD candidates and thesis-route master's programs. Interestingly enough, most drop out of the program after completing all the course work and all the data collection and analysis for thesis/dissertation, which suggests that the problem is in the writing stage—though this is seldom recognized in the literature, and often not even by the students themselves! Reorienting graduate students to the different nature of sustained writing projects could assist many more students in completing their graduate degrees.
The guide is available free from EssentialEdits.ca/ThesisStrategies.pdf.