Inappropriate terminology was a bigger problem though.

I once sorted out a guy's problem with (RiscOS product) Datapower even after discovering he didn't really know what windows or folders were: "Click on the hard disk icon. Have you got a window of folders?" -- "Don't blind me with science, son. I've got a rectangle of suitcases." We went through the whole problem with me telling him which suitcases to open and what rectangles would appear.

Peter