It's scary to think that this guy who was just shocked to discover a very basic concept of object oriented programming (polymorphism) has written his own book on iOS programming:
I also don't like how your comment tries to make fun of his efforts to learn something new.
The problem is not that he's learning, he's teaching.
Sorry for the confusion ;)
The blog entry is great in that it shows how collaborating over the Internet can lead to improvement but it's indeed a bit concerning that someone who didn't know what polymorphism was had been publishing a programming book.
Validity is a binary state. Don't modify it with an adverb.
Then everyone is surprised when critical bugs come to light in Ruby stuff.