I'm considering a used tilt-shift lens and I want to make sure I give it a good looking over before I decide whether to buy it or not. I've never used a tilt-shift lens before, and I think it takes some practice to learn how to use them well, so I have no idea whether I'd know a good lens from a bad one when I had it in my hand.
There's already a question about evaluating used lenses, and the accepted answer is excellent and really thorough for the general case. But I don't know if there are any potential problems or issues that are specific to these kinds of lenses that I should look for in addition to the list in that answer. I already know if I want a tilt-shift lens,1 and whether this particular model is one I'd like,2 but I don't know how to tell, when I show up to the List residence and Craig hands me his actual physical lens, whether the one I'm looking at is a lemon.
It seems pretty straightforward that I'd make sure the mechanisms all work smoothly and throughout their full ranges. Are there additional things I should be on the lookout for?