[Leon]

I think you need to look at what cards you never see in high grade to answer this question. A few that come to mind are:

T213-1
T216 Virginia Extra
E107

Any that are paper thin will be condition sensitive. Also, E105 since most have that nasty crease in them.....If I had to pick from the original list of reasons why they are sensitive it would be their paper stock and method of distribution, though this might not apply to E107, as I know a bit less about their distribution methods....but they are rarely found in high grade. Good question.