I agree with this guy and I think one of the reasons for this is that a lot of the people that buy into this will do so casually: as (a) a one-off at a low pric

I agree with this guy and I think one of the reasons for this is that a lot of the people that buy into this will do so casually: as (a) a one-off at a low price. They also (b) may not be willing to sit for an hour watching. Agreed with making some teaser videos -- perhaps the first 15-30 minutes of the video they are interested in. Then bring up a call-to-action and measure your conversions. Due to the possibility of people watching this at lunchtimes at work it might also be a good idea to (1) create some way for people to bookmark where they watched up to, and (2) make the site look as work-like as possible.