Could it really be that on their first day as a teacher (or when they first get promoted to head or deputy head) they are handed a cane and told they can use it even though they have never caned anyone, been caned, or even witnesses a caning before?
Perhaps teacher training colleges used to do a couple of seminars about how to use the cane; I expect the trainee teachers had to break up into pairs and practice on each other, that way they would have some experience of using the cane and also know what it felt like before using it on an actual student.
Or perhaps this is why state schools preferred to cane boys’ hands or slipper their backsides: this takes much less skill and it is much harder to go wrong.
It would also be interesting to know how the cane manufacturers and suppliers tested their products…