[Bob Childress]

ZFs do seem to require good preparation plus careful precise shifting to avoid problems. Several methods to eliminate vagueness in the shifters have already been presented by Ross, Gary, Ian, Jim, and myself in a prior thread. I would add to the comment Ross made that fast shifts require a solid shift mechanism. And, a reverse lock-out also seems like a good idea.

As for a careful shifting warning label, here is a picture of a metal and silkscreen warning label from a GT40. Maybe someone knows the story behind this tag.