"Entertainment" level of the classroom experience has been shown to affect over-all instructor ratings (Costin, Greenough, & Menges, 1971). The famous "Dr. Fox" study (Naftulin, Ware, & Donnelly, 1973) found that an enthusiastic actor was highly rated on teaching quality despite a lecture intentionally devoid of content.
All from (Wright, 2006, p. 418)
Naftulin, D.H., Ware, J.E., & Donnelly, E.A. (1983). The Doctor Fox lecture: A paradigm of educational seduction. Journal of Medical Education, 75, 138-149.
Costin, E., Greenough, W.T., & Menges, R.J. (1971). Student ratings of college teaching: Reliability, validity, and usefulness. Review of Educational Research, 41, 511-535.
Wright, R. E. (2006, June). Student evaluations of faculty: Concerns raised in the literature. College Student Journal, 40(2), 417-422.