I agree with you completely. I am not a big visual learner, so personally, visual note taking is not a good method for me. However, for some students, it probably works very well. Students should have the choice of how they want to take their notes, and should use the method that works best for them. It should not be mandatory that all students use the same methods, because all students learn differently. Introduce the method, and then leave it up to the students.