The value of blind fold chess

What is your opinion on how helpful it is to train to play blind?

Before there was such thing as engines, I have heard one grandmaster (can't remember who)  said the best way to read a chess book is to not use a board, and the values of blind fold chess includes being able to read books without a board  (The book logical chess move by move was actually meant to be read without a board as it has a lot of illustrations every few moves).  So I assume that if one is capable of reading and playing blind, it can improve one's calculation skill drastically.  I know in real life that there are players who can do this naturally, and there are also those who is capable of doing it after some training.  I also know at least one grandmaster who can't do it because the short term memory is not good enough.

So do you think it is worth it to learn to play blind?

It's certainly worth giving it a try.  I am able to read many chess books that have occasional diagrams without setting up a board. But handling a whole new game is 100 times harder. 

It must be a great advantage to be able to see the game blinfold. It is like being able to move the pieces as much as you like without suffering from an horizon effect.

I think that it is an ability all on its own. I know of players weaker than me that can play blindfold or analyse the position without looking at the board but I am completely hopeless at it. I couldn't even do a two bishops mate. I am afraid that trying to teach me to play blinfold would be like trying to teach a dog to read.

The downside is, if you can play blindfold, you would probably never get to sleep after an OTB loss. I sleep like a log because it is hopeless even trying without getting a board out.