Given the intended use I would be very wary of the screens and their locations. Not only do you want to be sure that the screens and projectors have appropriate physical relationships for throw distance and angles and are of the correct size for the audience area, but it sounds as though light on the screens and maintaining a usable contrast ratio may be a concern.
This is one area where the wax paper screens really concerns me. Other concerns on that include how fragile the screen material is, how well it prevents hot spotting, what kind of viewing angles you get and what it does to the light output from the projector. The overall issue is making sure that the entire audience can see what is on the screens and not have it washed out or impossible to tell what it is.
The video 'wall' idea is interesting. I looked at the link you provided for the concept and it sounds like it is not actually a video wall where you split an image across multiple screens as much as it is ten different shots of the same image; different angles, portions of the image,
etc. If this is wrong and the idea really is a video wall with a single image across multiple displays, then there may be some problems with the proposed approach.
Another consideration is that the application shown in the link provided was for a single person viewing from a short distance from the displays. Not knowing anything about your venue, you may want to consider how that translates to a larger audience. It is possible that some audience member further away may not be able to discern much from the images, they may just be a blur of color and brightness. It is even possible that this could become more of a distraction for some, not really being able to discern the images but drawing them away from other activities on stage. This is very venue and application dependent so it may not be an issue for you, but sometimes things that work wonderfully in smaller settings simply do not translate well for larger venues.
As noted, you will have some resyncing occurring at the projectors when you switch between sources. Using switcher/scalers or seamless switchers could prevent this but would also be more expensive and require running RGBHV/VGA to the projectors. The concept of putting the same files on each DVD is interesting, but unless the DVD players are synchronized you would have differences between them.
Which goes to an important point for your particular application, that you may not care about many of these aspects. In fact, having images poorly registered, delays between different images, hot spots, etc. may actually be a desired 'effect' for this use. And you may not care if the effects differs over the audience area. The one area that may be of concern is making sure that the images are easily visible over the audience area so you might need to verify the screen material, projector brightness and locations and how lighting and set pieces impact the projected images.