The Envelopener is a letter opener/paper cutter that's favored by origami folders because it cuts along folds precisely, there's no way you're gonna injure yourself, and it's highly portable. It's sold on multiple origami sites. You can see a video of it in action on Youtube. There's no brand name on it, and you can apparently get these things branded yourself. It appears to be of European manufacture.
It works like a dream. Most of the time.
Then there are the times it stubbornly sticks and won't cut at all. The cutter basically has a fixed exacto knife blade in it, and plastic guides that separate the layers of paper around the blade. But sometimes, both layers can go through the same channel (so no cuts), or the paper binds up against something in the channels (so sticks). Any ideas on fixes or techniques to get around these two issues?