Also castling is an efficient way to connect the rooks to defend the back rank and to support each other when competing for open files.
Is this a good chess strategy?

Also castling is an efficient way to connect the rooks to defend the back rank and to support each other when competing for open files.
Everybody at chess.com defends the 8th rank like it is bank full of gold.

You might have a look at the Steinitz Gambit: http://chessskill.blogspot.com/2013/04/lesson-of-week.html
I just love it when somebody edits out the part of what I wrote that specifically addresses their rebuttal, don't you?
I'm not certain what you mean. I did not offer a rebuttal.
You'll notice that when masters like Steinitz don't castle, there are usually one of two things going on:
First, and most common, the situation in the center is stable and/or locked. In other words, the king is not in danger in the center because it is difficult for the opponent to get at it there. The opponent can not open up the position favorable.
You might have a look at the Steinitz Gambit: http://chessskill.blogspot.com/2013/04/lesson-of-week.html