I do think that, like some people point out, they take some short cuts and don't think through some of the plot devices and story elements as a true fan would.
If they wrote the script and the. Filtered it through some hardcore fan focus group they coud probably work out a lot of the things that even the lower level geeks would pick apart.
Of course, Lucas was the original source material for Star Wars and he still managed to ruin his own franchise so why should I expect the people making the movie for the fans to get the fans involved in order to make it more enjoyable.
Imagine if a writer/director/producer actually trolled a bunch of discussion forums like this in preproduction? Some movies might be a lot better.