But I think you two are absolutely right. I am really a fans of the prequels as well, but when it comes down to it, they are really not designed to be watched before the classic trilogy, for they reveal so many informations that shouldn't be available for first time classic trilogy watchers (I'm thinking follow up generations here). So I think you two are right that they really don't work as 'one big film' when watched in the correct chronological order of story events.
Jimbo, you have to think about it from the point-of-view of people watching the movies for the first time and how the story works out then. If there are too many spoilers in there, all those great moments us StarWars veterans had during scenes like Vader revealing him being Luke's father will be ruined for them - now with the '2oo4 Editions' they won't even be able to avoid those spoilers by watching the classic trilogy first.
Much of the new stuff seems to be tailored for viewers who already have seen the classics a dozen times.