The idea is to have the possibility to define a sequence of videos. It should allow combining several smaller ones into one logical group (scenario) that would be possible to play in a row, just on one click. That feature would create a lot of flexibility and radically reduce maintenance costs.
Actually, there is no possibility to hook to any event and recognize that a playing video has been finishing and automatically start playing another in a row.
The security would be based on the same rules as private videos have today. It means that also each sequence would have public/private status (the only restriction would be that a public sequence can’t contain a private video or a private video without a public feature like a public thumbnail/preview).