I have students submit video a lot, and in normal assignments I can limit that submission to Media Recordings only. I do not allow them to submit through file submission because this usually forces me to download the file most of the time, and I can't just play the video in browser. When it comes to discussions, it's a complete free for all, and I need more control! The whole point of a discussion is to create a place for conversation, and if students have to download other student's videos rather than just watch in browser, then that tends to discourage the watching of them. Also, I really really don't want all of these files getting downloaded on to the local computers.