Truthfully I am not as well versed in RGSS scripting as I wish I were, but generally speaking, good code should explain itself to those with a familiarity with the language. This is why you may on occasion see scripts provided with little to no instruction or commenting. Some of the better and commonly used scripts used are fairly easy to put into place with a simple copy+paste. They are then modified to suit your needs in such ways as modifying certain variables, commenting out unnecessary portions, and/or simply excluding scripts entirely to suit your needs. It's not something one should expect unfortunately.
If you plan on using RPG Maker for an extensive project which you'd think requires customization via scripting to reach what you've envisioned, then finding yourself familiar with Ruby and the syntax of RGSS specifically will surely help you out tremendously in the long run not only with creating your own scripts, but with aiding you in a better understanding of how scripts made by others work as well.
EDIT: As a side note, if interested in learning how to utilize the scripting language used in the RPG Maker series, more specifically RGSS3 for RPG Maker VX Ace,
Trihan has a excellent guide to get you up and running. It's located alongside many other examples and resources to learn from in the
Learning Ruby and RGSSx section.