If you smuggle through once, why not both directions. I have a small knife, 1 7/8 inch blade, that I usually remember to leave at home. On the three or four trips where I realized that I had it with me, I have never had a problem getting it through security both ways. In one case, it wasn't until I set off the metal detector that I realized it was in my pocket with my change. The screener asked me to take everything out of my pockets for hand wanding. When I pulled out the change, my knife was there too. So I was there standing with my arms out, with a handful of change and knife, wanded successfully, and sent on my way.