What a thorny issue, tachyon!
It's hard to define OT properly.

• On one hand, some questions in the Monastery appear to be OT to the monks who can better discriminate between the subjects. Take database questions, for example. A fair amount of them are just SQL or normalization issues, but the poor guy who is sweating at the problem can only see a stubborn Perl script that refuses to work. When I see the question, I can realize that the mistake is in the SQL syntax (or the Apache configuration, or the OS environment or whatever) and give an answer. However, I am sometimes reluctant when my answer doesn't have any Perl in it. I usually don't mind when I acknowledge that the requesting Monk is not trying to cheat me into answering a database question, but (s)he has really a problem and doesn't see the end of the tunnel.
  Personally, I feel that I should answer the question, if I think it's a honest one and I know the answer.
• On the other hand, there are questions that include a truckload of Perl but are actually about something else, and what the Monk really wants is only a free evaluation of a secondary aspect, such as the database backend or the web design. Those posts are seldom recognized as OT, and usually find some answers in the Monastery.

With the above analysis, I declare my ignorance in recognizing all OTs, except perhaps the blatant cases ("How do I set my Apache?", "What is the syntax for the <table> tag?"), and I will continue trusting my guts.

Coming to your tutorial, I would be glad to see it in the appropriate section. I agree with your reasoning that it is a relevant topic. We have had some nodes dealing with editor features (I plea guilty of this sin), and somebody feels that they aren't orthodox. My idea is that since we write programs, and we use editors to do that, the topic is relevant and important. Our programming is not in a void environment, but is intermingled with editing, shell, databases, OS, hardware and more. Taken one by one, these subject are OT. When they are related to Perl, however, they can be as important as knowing the syntax of split.

My conclusion is, Go for the tutorial, and many thanks for writing it!

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