A couple BST threads discussed WST and Cylinder Transfers, so I hope that this thread can help.
A WST is usually caused by a printer placing a sheet of cards which are not quite dry on top of another sheet. A faint amount of ink transfers to the other sheet. WSTs are usually very faint and lacking in clarity.
ICTs are quite different. Quoting Ron Kornacki," ... offset printing (is) where a plate image transfers to a blanket cylinder and then onto the paper. If the paper is not fed, the blanket image will transfer to the impression cylinder. If that happens, a reversed image would print on the back side of the paper the same time the image is printed on the front. Normally the impression cylinder would be cleaned if a misfeed happened before feeding another sheet in to avoid the error reverse printing." If the cylinder isn't cleared, you get an Impression Cylinder Transfer.
The ICT images are reversed, just like the WSTs. However, the ICT is much darker and more clear, as it didn't transfer from a different sheet, but was printed directly on the back of the sheet being printed.
For comparison, here is a WST (Bescher) followed by an ICT (Bowerman):
scan0001.jpg scan0002.jpg
scan0003.jpg scan0004.jpg