This thread made me realize that we all tend to be less-than-swift when handling a new, unfamiliar tool. Think about the difference between getting into your own vehicle, and getting into a rental car when you first drive it out of the rental lot.
It is probably better to avoid lending any knife. If it's a folder, open it for them and hand it to them handle first, and tell them you'll close it for them when they're done. And do ask them what their plan is.
I already carry an EDC plus a small-bladed 'sheeple' folder. And now I have to carry a cheapo 'lend' knife as well? Where does it end?