Regarding Visual Approaches.
AS with any aspect of flying (even tying your necktie), you have to practice to get proficient and maintain proficiency.
Does visual approach experience in one plane transfer to another. I say: yes.
Can visual approaches be taught? I say: YES.
Can meaningful aids, such as distance vs altitude and ground speed vs descent rate be taught: I say: YES.
How much time would I guess the pilots involved in this accident spent on considering the visual approach? I say: negative ten hours.