Here's something I hadn't come across in the previous 18 years: someone who actually likes the scene in Jackson's Return of the King in which Frodo junks Sam.
As I recall at the time, even among the most enthusiastic movie-fans this generated more reactions of "WTF?" than anything else in all 3 movies.
It doesn't work dramatically any better than all the other places in these movies where the plot is run off the rails and then has to be hoisted back on if the tale isn't going to depart entirely from Tolkien's, leaving the viewer puzzled both as to why the story ran off into this ridiculous by-way and by the lack of internal plot-based explanation as to why it then reverted to form.
This addition makes J-Frodo out to be a credulous fool (in falling for Gollum's maneuverings); and if Frodo could do this, it undercuts the whole basis of his relationship with Sam, which is based on an absolute mutual faith, no matter how cranky Sam becomes (and J-Sam is abominably cranky).
Lesson: don't try to add more "dramatic tension" to a story that already has quite enough; don't imagine that "dramatic tension" consists of the heroes losing their nerve (which is what happens in most of these scenes); and don't tinker with a story you (the filmmakers) don't understand.