Final Course Numbers: What Did We Learn?

Ultimately, 29 students passed our two online sections of English 102, with another ten students submitting withdrawals over the course of the semester. An examination of the students' grades in relationship to their familiarity with online courses is very suggestive:

It seems clear that student success in these courses was in direct relationship to the students' familiarity with the online course experience. What does this suggest? Are the skills needed by students to excel in online writing courses so different from those needed in face-to-face writing courses? Does a certain type of student have a better chance of thriving in an online course?