Count me among the lazy ones! No, I do not turn my machine off but I am very careful. I have been impaled once. Lesson learned.
I know there has been a lot of discussion about canned air used to clean the bobbin area. I spoke to my Bernina tech and he showed the class how to use canned air. Do not blow into the machine front to back! Blow from right to left. Take off the needle plate and blow from back to front. If we blow from the front, the lint, etc will travel back toward the handwheel and cause the problems we saw on another discussion here. We were also told to add a drop of oil everytime we add a new bobbin.