What is it...

Even having White isn't considered enough advantage to expect a win with perfect play.  I would think for a player to have a sustained 200 pt. superiority, the advantage must be more than barely there.  I can't believe that a 2600 player can't calculate as deeply as a 2800 player, though I can believe that something in the evaluation of the calculated positions might be better for some reason... it's the reason(s) that perplexes me.

Interesting point if view. 

By the way, anybody tried to teach dolphins to chess ?!

How to design a " mouse " for dolphins ?

There can also be differences in chess education. The players from countries of strong chess culture (such as Russia, Ukraine etc.) typically receive strict formal training from early age which may not be case for GM's from other countries.

Take Michael Adams for example, obviously very strong GM at 2700+ level but still level below the very top guys. From what I've read I've understood that he hasn't have such a formal training. Here's a quote from his Foreword to Ivan Sokolov's book 'Winning Chess Middlegames': "... I proposed a certain plan in a middlegame position; Ivan looked a little confused, his eyebrows started twitching and he responded ' yes, but this is just a normal position'. In his chess education, he had broken down structures into various typical situations and analysed these. The english school of chess had a slightly more chaotic approach." One may speculate that maybe Adams could have been even stronger with more formal schooling.

Next story suggests it may be possible to guess the opponents strength:http://www6.chessclub.com/news/990

That sounds convincing.   But does Norway have such a strong chess culture?  Armenia might since they produced two Petrosians and an Aronian, but I'm not sure.  The U.S. surely doesn't, but we produced Fischer.

Agreed. It's random. I hope someday we can have a champion from Zimbabwe. And that's not an insult, but a complement. Even from Nicaragua or Hawaii. Why not?

Fischer was a product of himself and the soviet chess school.

I wonder if a 2600 could be a 2800 the next day or week, and vice-versa... Or could there be a simpler explanation - like a fly bothered the losing side at a critical thought process... I don't know.

from 2500+ the knowledge of chess is more or less the same in any top chess player, the difference is how each one can use these knowledge, and that is the talent. You can teach ten students the same stuff, but only one or two of them gonna make it.

batgirl, without talent nothing happens. similarly, with talent and without extensive work being competitive at the highest levels may not be possible.

look at carlsen, he doesn't do that much opening work. he just simply knows how to play.

I wonder if the age at which grandmasters began studying chess to a deep level effects their potential at all. No doubt there just seems to be an upper limit to their peak all chess players reach at certain ages and just don't seem to improve any further. 

Would it be fair a statement should tests be conducted to say, GM's or chess players rated over 2600 have abnormal cognitive functions, clearly they possess a mental advantage of others?

If you begin to learn at early ages, what you learn becomes a sort of mother language.

I know GM Patrick Wolff who was rated over 2500, stated that after coaching Anand, he realized that he could never play at that level.

And when a GM says something like that, it means a great deal...!

But you get the same in sport as well - you get the "ordinary" international who is already so far ahead of normal human ability that it beggars the imagination, and then you get the once-per-generation or even -century luminary with whom even the run-of-the-mill international can hardly compete. At times like this I generally mention Bradman, an Australian cricketer from the mid-20th century. You don't need to "get" cricket to understand that if most internationals are happy with a career batting average in the mid-40s, and maybe half a dozen of the game's outstanding  performers ever have managed the low 60s, then Bradman's average of 99 marks him out as something so far out of the ordinary it's hardly even on the same scale.

The job of a coach is coaching, to teach students to be better than the coach. The students hopefully are better than the coach.

Most of us, with every respect to our teachers, have more knowledge.

So to say a coach should be better than the students is misleading. At one point the coach is better than them. But after it, they could be much better.

A good number of IM or GM (2500-600) knows a lot of chess, but his achievements were not so good in tournaments. Instead of that, they became great chess writers...

bean_Fischer, I think what was being expressed was that a GM, a player of extraordinary strength, talent, knowledge and ability, can recognize that even he can't grasp, or couldn't invest himself so deeply to grasp, what a super-GM already has.  Maybe the difference is so inexplicable, yet so real, that one is just aware of it without understanding why?

I think that one of the things that differentiate a GM from a super-GM is the ability of an s-GM to realize not only how to break the rules but precisely when to break them.  The accuracy of their play is almost instinctive, but does decline as they age, so it isn't a right, just a privilege they enjoy for a little while.  But in what part of the psyche does this reside?  And why will it elude a 2600?  I have no idea.

Let me try to explain with a music example. The Beatles were 4 boys without music knowledge, only knew 3 or 4 chords at that time. They never went to a music institute nor had voice tutors, and they hadn't their own instruments at the begining, but they changed the music in some way. All because their talent and willpower. Maybe a similar example are Capablanca and Morphy, not so much knowledge but a great capacity...