I'm interested in this notion that the story is 'stretched'.
The title of this thread assumes it, and so did Pan just now. And most people who haven't seen the film (and some reviewers who have) grumble that the filmmakers are putting in things which aren't in the novel, and are stretching the material.
It seems to me that it's a misconception based on the differences between novel and film.
When Tolkien writes, 'The Goblins chased the Dwarves and captured them', how much screen time should that chase take? Should it take the two seconds it takes to read that sentence? Or is it legitimately developed into a massive chase sequence - because we're watching an action film?
When Tolkien writes, "All the Dwarves grumbled and groaned, but eventually congratulated Bilbo", what does that mean? What do they actually say? And if the screenwriters are going to come up with things for them to say, isn't it better if each dwarf has his own character, so that what he says has some emotional heft (funny, sincere, etc)? Complaining that Tolkien never wrote Ori as a hippy, or whatever, is meaningless because he only sketched the personalities of a couple of the 13 dwarves, other than Thorin. But they have to have things to actually say.
When Tolkien doesn't really describe the Battle of the Five Armies, because Bilbo is knocked out, does that mean the filmmakers should not film the Battle? And if they do, how long should that battle take?