In my 14 years of online teaching I find it EASIER to manage conflicts with students ONLINE than face to face.
Email gives me time to craft my response for MAXIMUM impact. Losing control of the situation is almost eliminated because I set the pace. This is especially important when a student is trying to "push your buttons." I can cover all bases and nip potential problems in the bud.
While I am good at thinking on my feet, I prefer to use the written word when dealing with uncooperative students.
