There's not a lot they can do to trim down the length of the attraction while keeping the same ride system.
There are two sets of ride vehicles in the building at all times. While one is finishing a show, unloading, loading and running the first film in Theater 1, the other set is going through the diorama and watching the Theater 2 film. Theater 1 is actually empty for only a few moments between one set of cars exiting and the other set entering.
The pause time for unload and load can't be touched because they have to account for loading and unloading a totally full theater, 6 wheelchair Guests, etc etc. So the only place to trim time off would be the Theater 2 film, but that would also require shaving an equal amount of time off of the first Theater 1 film.
The Theater 1 film is only about 4 minutes long, so at most you could shave 8 minutes out of the overall attraction if you totally eliminated the Theater 1 film... (four minutes saved in Theater 1, four saved in Theater 2)
Of course you *can't* get rid of the Theater 1 film entirely, otherwise you're just turning and going straight to the diorama...
-Rob