Well, not myths really, but it's sometimes worth challenging cherished notions
Deep down, students know what's good for them
In "Student interest and choice in programming assignments" (Journal of computing in small colleges 26, 6 (June 2011)) Lisa Torrey surveyed 14 students to find out what motivates their choice of programming exercises. She'd hoped that students would choose programs at the optimal level of challenge but found that "students disproportionately chose to write less challenging programs than their interest patterns had suggested". She felt that "many students would choose easy programs that happen to contain other interesting factors".
In March 2014's "Assessment and Evaluation in Higher Education", Felton and Mitchell claim (providing some evidence) that "Faculty who lighten workloads and inflate grades buy high SET [Student Evaluation of Teaching] ratings and popularity for their courses". Older staff are less prone to doing this.
The more a topic's taught, the more students will learn
In "When do students learn? Investigating factors in introductory courses" (Journal of computing in small colleges, 2012) it said - "we found that instructional time spent on a topic often has a far weaker connection to student learning levels than does instructor emphasis. ... Just spending more classroom teaching time on a concept will not improve student learning as much as an instructor placing greater emphasis on that concept ... For CS1, there were few topics for which there were statistically significant correlations between instructional time and student learning".
The better the teacher's presentation, the more the students learn
In the May 2013 issue of "Psychonomic Bulletin and Review" it reported that "When a presenter is seen to handle complicated information effortlessly, students sense wrongly that they too have acquired a firm grasp of the material". They're more confident, but perform no better.
In "The Times Higher" (30/5/13, p.7) it's reported that "lecture fluency did not significantly affect the amount of information learnt".
Clarity is good
In The secret life of fluency Daniel Oppenheimer wrote that for some exercises, "participants were significantly more likely to detect the error when the question was written in a difficult-to-read font. This suggests that they were adopting a more systematic processing method and attending more carefully to the details of the question".