Agreed, and I know of no good beginner friendly documentation for the scripting. There are a lot of details buried here in the forums, but it would be nice to have a proper tutorial. Some similar request was in Is there a tagging script tutorial?
I have seen it many times that users are overwhelmed with even simple tagging scripts. I think that’s sometimes easy to overlook for someone with a programming background, but if you have zero experience with this something like $num(%discnumber%,2) - %artist% - %title% can be frightening. And then even something like “I want to change this to not include the artist” can be a challenge 
I have tried a couple of times dissecting more complex scripts into it’s individual parts to help people actually understand the script, e.g. Help understanding Picard naming script system for noob or Help with script for filenaming scheme
I think a tutorial should look a bit like this, starting with a simple naming scheme, examples how the result will be, and then introducing more and more complex ideas. Now we just need someone to write it 