You bring up a major distinction in HE between the role of the researcher who has to teach and the teacher who has to research. Because of the very hit-and-miss nature of hiring an excellent researcher who may or may not have good andragogy skills and the rise of management of education, there has been a great proliferation of teacher quality programmes in the past decade. I would hope that the political pressures on expert researchers to at least review their teaching style would have led to many changing. However, researching expert researcher teaching style is problematic. I did find a Turkish phenomenological study that aimed to begin this research (Tunca et al., 2015). Of course, there are dozens of texts and studies designed to show university teachers without an education background ways into the Scholarship of Teaching and Learning. Richlin’s book is a typical and good example (Richlin, 2006).
Should researchers know how to teach? This wonderfully ethical question hits hard at the nature and structure of the research university. Anecdotally, we all know of researchers hired that have to do a few classes who seem to resent that imposition. Politically, removing them from their posts would be difficult as their prime mandate is research. Equally, absolving them from all teaching responsibility would raise questions about the relationship the university has with its teaching responsibility.
I’ve no time to research the situation in the universities right now, but for compulsory education, Hattie’s (2009) meta-analysis shows dozens of studies that point to the teacher effect being one of the main factors that influence learning. His book ‘Visible Learning’ is fundamentally flawed but nevertheless remains one of the most important books in education. The accompanying website: http://visible-learning.org/ gives a good taster.
Hattie, J. (2009). Visible learning. A synthesis of meta-analyses in education. London: Routledge.
Richlin, L. (2006). Blueprint for learning. Sterling, Virginia: Stylus.
Tunca, N., Sahin, S. A., Oguz, A., & Guner, H. O. B. (2015). Qualities of ideal teacher educators. Turkish Online Journal of Qualitative Inquiry, 6(2), 122-148.