I've been wondering about this for quite some time... in fact ever since I read Buckley's Strange Fascination. What is the purpose of the dancers in Glass Spider concerts? I've been formulating a theory on this, and after wathing the video several times I think I'm ready to post my Lovestory of a Popstar and Outcast. (It must be noted that I have only seen the video, which means I do not know the entire story. Also, this interpretation is in many parts conflicting, as it is not even trying to be a final interpretation).
For the story, let us start from the beginning. After Carlos' solo, four people slide down from the Glass Spider. These people are outcasters of the society. They admit themselves that the "are made from the wrong stuff." It ought to be noted here that the roles of these people do not stay the same troughout the concert.
After the wrongs stuff have sun their song, we have Glass Spider, and Bowie's messianic entrance to the stage. Note that here the roles of some of the dancers change. They're now Bowie's publicity people or something like that instead of the wrong stuff.
Day-In Day-Out in my opnion offers nothing important for the story, but after that we have the part where the story really begins: Bang Bang. During the intro of the song, we see Bowie the star trying desperately establish somekind of a connection with normal people of the crowd. The dancers, now representing the corporate forces, try to stop Bowie. Eventually bowie manages to grab a girl and bring her to the stage. The "corporates" prepare the girl to be with Bowie, she resists at first but eventually we see Bowie and the girl dancing together.
Next song down the line is Absolute Beginners, which IMO could have two meanings: 1) it is David's way of telling about the loneliness of the popstar. All the people around him dance affectionately, moving ridiculously slowly, and they basically refure to have no connection with Bowie. Or 2) Melissa (the Dancer) has noticed how desperately Bowie wishes to be with her, and plays with his feelings. For what reason I do not know. One thing that also should be noted is the girl in the wedding dress that appears in the stage near the end of the song (which dancer that is, I do not know).
Loving The Alien is an interesting and strange song from the story's point of view. We see Bowie kneeling in an oriental prayer-position, which might very well be a sort of purification before marriage. The lyrics of the song also interact with the story here: both Bowie and Melissa are "aliens" to eachother's worlds. Their marriage is a leap to the unknown, a thing that the "blind" dancers in this scene might reflect.
Loving The Alien is followed by two songs that do not IMO have any specific meaning for the story, China Girl and Rebel Rebel (the latter being one that was added during the tour). However, in Fashion we return to the story again: Bowie is challenged by Melissa's friends, into a fight to prove his worthiness (the wrong stuff have their pride too ). Notice the end of this scene, after David has knocked out his two adversaries: first Melissa is clearly angry at David, but then for a short moment before David faints, the two dance together.
Never Let Me Down is another hard-to-grasp song. It clearly has some meaning: there are only two people visible on the stage, Melissa using some kind of ... drug? to ease David's visible pain. However, I'm not sure about the deeper meaning of this: is David unhappy and Melissa is using some kind of drug to keep him satisfied? (it seems very much like she is forcing David to breathe whatever she is giving though the scene). Or is it something else along the lines of being intoxicated with love? My first theory seems more plausible, but I'm not sure.
The next song, "Heroes" is pretty much the end of the story as well. Bowie is tied by two spaceman-like creatures, and when he sings "nothing will keep us together", Melissa sets him free. This is probably the easiest scene to understand: there is a video of a man waving goodbye, and there is Melissa setting Bowie free. It is also interesting to notice that near the end of the scene Bowie starts smiling, which he has rarely done bifere it on the concert. After that he wawes goodbye to Melissa.
This in my opnion was the end of the story. However, if one whishes to expand it, it should be noted that in the next song, Sons Of The Silent Age, Bowie is literally pulling the tricks on another woman.
So, what do you think? Am I right, am I wrong, did I miss something or am I just plain pathetic?