He tells you that the slides SHOULDN'T stand on their own, because an integral part of a class is, well, the teacher actually teaching. The issue with posting the files online is that some students get the mistaken impression that they do cover all the necessary information in class (they do for many other classes, at least), so it is better to not make the files available than get students _thinking_ they were finding all your material.
The audience for slides-alone vs slide-accompanying is vastly different. I often see them confused when a presenter has a 12 point font on slide meant for 100 people, or when I download a slide deck and there is a single word slide. Doesn't jive.
We need both formats.
The medium is the message, if the medium is slides plus presenter, the lecture needs to be recorded.
We are at this amazing point in history where the avenues for communication currently outstrip our ability to use them. We should all be finding ways to fill that gap.
