Has issues with a can-opener. Remember the can popping open.
I think that part of his problems with the can opener had to do with the fact that Ennis was undressing near him. A little distracted/ nervous maybe. He also seems to be left-handed, which can make can-openers designed for right-ies a little tricky.
OK, I just introduced the feather topic (yes out of curiosity), but also because I'm curious about some of the little details from the book that got omitted in the film. I'm also curious about things that have gotten displaced (including dialogue). Clearly, much of the dialogue from the motel scene in the book got spread out a bit to some of the different campfire chats in the film (including the story about Earl, the "if you can't fix it, you've got to stand it" line, etc.).
Here are two things that stood out to me or seem interesting in terms of dialogue. On Brokeback during their first chat on the mountain side after the first tent scene, in the movie it's Ennis who says it's a "one shot thing", but in the book it's Jack who says that. And, in the last argument scene in the film Jack says "there's never enough time, never enough" in his frustration with Ennis, but in the book that line comes from the narrator describing their love making. I guess the meaning remains about the same in this second example.
And, I've been wondering how the filmmakers wove that beautiful line from the book about Ennis being so happy he could "paw the white out of the moon" into the imagery of the film. Moonlight seems to be a general symbol of happiness during their love scenes, etc. But, I've been thinking that the general idea of that sentence in the book is conveyed pretty well in the 'prayer of thanks' moment when Ennis is so contented gazing 'up there in heaven' perhaps thinking about pawing the white out of the moon...
Also, at the Thanksgiving dinner when Ennis tells his story about his rodeo experience he says he 'didn't have no wings', which seems to be perhaps a displaced reference to that awesome line in the book about the time Ennis punched Jack. "Ennis had suddenly swung from the deck and laid the ministering angel out in the wild columbine, wings folded."
OK, I know I'm way over-analyzing things, and maybe stretching a bit. But there really are more examples of things from the book that seem to pop up in alternate places in the film. Interesting.