What is Blindfold play and Calculation play? I have no idea, so maybe if someone enlightens me, I can start arguing about it.

blindfold play is when you play blindfolded

calculation is when you calculate moves in your head

@stocke. When you play blindfold you must imagine where pieces are. When you calculate, specially tactics, OTB, as you can not touch pieces you must calculate several moves ahead. Blindfold is calculating the whole game ahead.

Yes, IMO they are both related and playing blindfold is good training for caculation. They are other more simple technics. I.ex. look at a certain position in a diagram during X seconds and then try to reproduce the exact position over a board.

I've just posted my first blindfold game, It's so difficoult to play all match without looking the board, I missed a lot of winning combination, with a player weaker than me, so stressful.

You "put on a blindfold" for the privilege of playing 500 points weaker.

Kasparov said something like that, and I find it true in my experience.

If a player has difficulties preforming what I call "clean" calculation (visualizing a line once and being confident enough that they don't have to calculate the very same line again to be sure) then I think you can gain a good amount of strength by practicing blindfold or similar visualization exercises (like playing through a game score without a board as far you can).

I guess I should try that sometime.

For me depends on the level, Kasparov couldn't play a blindfold game against someone as strong as he, but with 500 points less yes, IMO a player in a range of points from 1600 to 1800 points can play blindfold also against someone with 100 points less and win.

It's an interesting quote.  I'd definitely be interested in testing how much it drops different player's abilities.  Other than visualization ability I think general knowledge and style would matter too.  I would guess that for most player the more you're able/comfortable in playing positional positions the less it would drop your rating.

Are you really an NM?

Never played blindfold chess and I don't think I can do it. It calls for great powers of visualization and a really strong memory. My view is that calculation and blindfold chess don't equate with one another. I can perhaps work out a few moves ahead - very few - while looking at the board but to do it blindfolded requires something extra.    

chess.com asks for proof before you get the NM, FM, IM etc in front of your name.  I mean... they don't do a DNA test :p but it's pretty reliable.

Like any other skill, blindfold is just a matter of practice.  I learned as a young player, playing against my mentor in the car on the way to tournaments.  At first I couldn't follow the game very far - if you lost the position, you lost the game, it was resigning - at first, but gradually became able to keep it in mind, to play better at it, and finally to beat him regularly - at which point we quit playing!

I think there is some advantage to it in learning to visualize positions, but not necessarily a big edge in calculating.  It's more just being able to think about a position without having it set up before you.

Kasparov certainly wasn't giving up 500 points blindfolded, and I'm certain he NEVER said that.  Perhaps 100 points, probably less, depending on the time limit blindfolded.  The faster, the weaker in relation to sighted.

I'm pretty certain he said it--I just have to find the quote.

Just 100 points weaker when playing blindfold? I don't think that would pass any GM's smell test.

Maybe one will pop in and give her opinion.

It's worth noting that the only blinfold games Kasparov ever played publically were in a 10 game clock simul in Hamburg 1985 (8 wins, 2 draws)

There's a lot of superstition regarding blindfold exhibitions given that many players who gave them developed mental health problems/died young etc. They were even banned (or at least discouraged) in the USSR I believe

For me, blindfold chess is no different from regular chess in terms of how well I play. I play at the same strength, though perhaps a little bit more slowly. This has always been the case, even when I was a much weaker 900-level player. I typically win blindfold games against any class B or A player, despite only being Class C myself. I have never lost blindfold games against anyone but a master.

Blindfold simuls are more difficult. I seldom get a chance to practice these, but 2-3 games at a time is probably my max right now, and in this case my playing strength does drop a bit.

Kasparov made it hard on himself in that simul. Unlike a normal simul where the player moves to a board and the opponent must move, he allowed them to send their moves up to him when they were ready.

Mirroring, I suppose, a normal-sight clock simul.

There's some video of that one out there somewhere. Not exciting to view, but interesting.

I saw Natalia Pogonina somewhere here on chess.com, claiming she could play 2400 strenght blindfolded.