Is it beneficial to play blindfolded chess? I've played only two blindfold games so far, but it was against someone who was maybe at a 1000 uscf rating strength, and hence was fairly easy to beat, and once against my friend, who's also rated about 1650, like myself. I also managed to beat him with a sneaky tactical shot, but it was a lot more challenging, as I found it hard to remember where certain pieces were. I've also read that while it benefits your board vision for tournament games, it puts too much strain on your mind to be beneficial overall. Is this true? Any other arguments for/against playing blindfold chess?
In my opinion

I cannot speak to the health benefits or drawbacks of playing blindfold chess (which I find to be, in my opinion, baseless).

What I can say is from experience. I have attempted playing blindfold chess when I was not a very strong player and found it challenging and not worthwhile. However, as my chess progressed I found playing blindfold to be a lot easier, and was even recently able to play a game to the 62nd move where I checkmated my friend. It took 90 minutes.

My main point is that that blindfold chess more than likely does not affect your chess ability. It is your chess ability that affects your blindfold chess.

Here is are some conclusions from an in depth study

Source: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2972788/

In their review of the literature, Hearst and Knott document a number of notable conclusions that may surprise chess players and non-chess players alike:

The general memory of chess masters, including those able to play many blindfold games simultaneously, is no better than that of the average person.
Highly skilled players can form long-term memories of full-board chess positions within seconds of viewing them.
High level chess skill (not just blindfold chess) requires a recognition-action repertoire of some 50,000 to 100,000 features of chess positions and associated responses.
Some of the strongest masters find the actual sight of a chess position to be more distracting than helpful when thinking ahead during a game.
Practicing blindfold chess improves sighted chess skill.
Some of the strongest blindfold chess masters claim that the strength of their blindfold play is similar to that of their sighted play.

Bonus material

In case you really want to read up on the subject: http://www.wjh.harvard.edu/~cfc/Chabris1999d.pdf