Be honest - could you really piece together what was going on in ROE completely without some outside review of the story?
ROE was still a good show, but large portions of it basically go right over the head of the audience leading to drawn out sequences just staring at the globe not really being able to understand what the images being used are about. To most people the show is just a bunch of different paced segments - not being able to piece together the meaning or relevance of the content used. Just knowing they go through this progression, with multiple different segments that build to a finale. To most people it's just a entertaining show because of it's good music, great presentation and moving experience the sum of the parts brings.
ROE works because even WITHOUT any of the understanding of the tale it's trying to weave, it's still an entertaining show with only 'some' slow/boring bits. You aren't hit over the head with this messaging or force fed it. You still get an entertaining show w/o because most of it is abstract... carried mostly by the music, not the video assets.
The challenge these kinds of shows (both River of light and Harmonious) have is the more visualization or concrete things (clear video, lyrics, etc) you put into the show (large video screens, etc) the more that content and it's purpose is in focus and challenges the viewer to grasp it's purpose. If I put up a video wall with just some big cycling of images on it... people are lured to look at it and go 'why?', 'what was that?' 'how does that work with X?'. Vs having nothing at all.. or just a tempo based lighting. If you insert a song with lyrics... the lyrics push their way into people's conscious, etc.
The less identifiable the visual or words are... the less it will risk detracting and derailing things if not done well or received well. You basically create a ton of liability to be more explicit and spinning a message the more you put identifiable visuals and lyrics into the show.