A sidenote along these lines - I've recently done an MSc, and found that the default approach to lectures is now to present slide decks. One of the profs, however, delivers a more traditional lecture, writing everything on a blackboard. I've found the second style far more effective, largely because writing caps the rate at which information can be conveyed. Because slides have no such bottleneck, I've found they're often misused and overladen with information which is skipped over too quickly.