Interview participants called the effort to achieve TD integration “challenging,” “head-scratching”, and “somewhat painful”, as it required them to move outside their comfort zones, both by exiting their discipline-specific approaches, and by working toward TD integration and extension of disciplinebased approaches. They reported that TD research required them to invest extra time and effort to learn about other disciplines and to figure out how to integrate approaches from different disciplines. One participant used the metaphor of having to speak in a foreign language all day to describe the effort required to engage in TD research. If you have some ability to function in another language, then you can see how fatiguing it is. You're tired by the end of the day.
