The best guide I found for this was Miyamoto Musashi's Book of Five Rings, specifically The Earth Scroll. Musashi compares carpenters to warriors. Both must keep their tools sharp. Both must keep their skills sharp. In our profession, it is not enough to learn every command in Perl without learning the most efficient means of utilizing those commands. By the same token, there are times when Perl may not be the most efficient solution, so we must learn to use other tools and master them as well.

Whether you are using Perl (sword) or other languages (spears, arrows, etc.), there are certain prinicples that you apply to complete your task (ruin somebody's day). These principles do not change with your tools, and rely on the tools and skills being sharp.

A snippet of the Earth (or Ground) scroll:

1. Do not think dishonestly.
2. The Way is in training.
3. Become acquainted with every art.
4. Know the Ways of all professions.
5. Distinguish between gain and loss in worldly matters.
6. Develop intuitive judgement and understanding for everything.
7. Perceive those things which cannot be seen.
8. Pay attention even to trifles.
9. Do nothing which is of no use.

I cannot recommend this book enough for any person in any profession.