The goal isn't to write pleasant code; it's to explore what's possible with the language, even if you should be slapped for using the techniques in a real project. Reducing LOC is akin to code golf; the shortening is an ends to itself, and sites like codegolf.com are essentially competitive problem solving with a very strange goal.
Tangentially: In a different subject, there was an ad hoc competition to write the shortest science fiction story.
One example is Knock, by Fredric Brown: "The last man on Earth sat alone in a room. There was a knock on the door..."
Another is Cosmic Report Card: Earth, by Forrest J. Ackerman. The entirety of the story is "F".
Whenever I see "Tutorial: X" on the internet I immediately think "What if a beginner read this".
Therefore whenever I see an article without a "Do not do this in real-life / production because..." warning I immediately take a negative view.
In this case I evaluated the site with that in mind, all the techniques are useful but the examples are pretty badly shoe-horned. There are much cleared ways to give examples of multiple assignments than the examples there.
Other things like writing methods on one line, probably useful in situations like defining error classes
"class MySpecialError < StandardError; end" but apart from that I frown upon it.
There is also the "Hey, this is a nested ternary operator" example which is... well, demo'ing nested ternary operators without a big fat "Do this in real life and people will hurt you" warning is a no-no in my book.
A bit rambling but I suppose to sum up my main problem with this was "Here are some things you can do" without actual discussion about when they are suitable, when they are not, and why this is so.
If you have to do stupid tricks such as concatenate statements with ; and create long lines, it's not a useful trick.
In general, reading even the original code, the author doesn't understand Ruby or OO in general. A number of the items would be one-liners with an improved application of theory rather than syntactic rewriting. If the goal is just golfing, then #map and possibly rockets would be better choices.
If I wanted less maintainable code in a shorter line count, I would use a mechanical obfuscator.
