Ok, so you know how a lot of car stereos have a removable faceplate? The theory is a thief won't bother stealing the radio because it's too much hassle to get a replacement faceplate.
What if folding bikes had a similar concept? Let's say the hinge needed a small metal part for the bike to stay securely folded. Without it, the bike just won't stay together. You would take this part with you when you lock up.
I'm sure you're thinking that the thieves wouldn't know about it until the bike is already stolen. I agree, it would take years before word got around that a particular folder isn't worth stealing. But I think so what. Eventually we wouldn't have to worry as much about our folders getting stolen.
[Yes I know, folders can go with me everywhere I go, but often I like to just leave the bike outside]
Good idea?