Now, now boys. Cocks away. Urea has a horrible affect upon lime mortar.

99% of Perl users will go through their lives without ever needing to know these obscure details. And on the rare occasions they ar bit by them, they'll juggle their code a bit and fix their problem without ever understanding the deep reasons behind what the did.

There is a temptation amongst those with deep inside knowledge to want to warn of all the traps and dangers--like over protective mothers with bikes & skateboards & horses. But conveying *all* the dangers and possible consequences in detail is just too time consuming, so they seek to codify them into simplified rule sets that must be blanket imposed on all.

They forget, that newbies like kids, need to learn from their own mistakes. It's not just a right of passage, but the best way to learn. They learn not just the solution to their mistakes, but how to approach solving problems. And how to form their own judgements about which precautions are always valuable, and which are just motherly paranoia.

Take that learning process away from them and you end up with rote-learnt semi-experienced programmers that are completely out of their depth the moment something slightly beyond your simplified rules comes along. Dead in the water with no problem solving skills to fall back on.

And when interviewing, they have no answers to the why did you do that questions.