On the AGMA Helical Gear Rating Committee we frequently deal with how to warn users away from potentially dangerous designs. Some years ago our wonderful chairman colorfully declared we should just adopt the warning from ancient maps of the then "flat world" and label the areas of concern as "here there be dragons." Eventually some explorer ventured "off the map," and if they came back the map got revised to reflect their account. The same thing happens in design, of course. Usually it is the result of an error or operator abuse.