This is not so sure.Take the example of Sutovsky whose rating 2 or 3 years ago was 2697,but at the end of 2006 he was rated 2607.You could call him a super GM in 2004 and a modest one in 2006,but I think it's the same guy.

But I still think a 50 point difference at the 2600+ level is significant. If we judge by head-to-head scores and common tournament results, a 50 point rating gap among "the stars" tends to reveal a clear difference in their relative strength -- more so, I believe, than among low rated amateurs. Consider Anand and Svidler (50 points) or Ivanchuk and Malakhov (50 points) or Ponomariov and Sokolov (54 points).

There are always some exceptions in cases when one player is very much overrated or another is very much underrated, but in general the ratings of GMs are more reliable than the ratings of amateurs because they tend to play more regularly (more data is available). The result is that rating points are somewhat more indicative of actual strength at the GM level than the amateur level. The ratio of games in which 1600 players defeat 1700 players is almost certainly greater than the ratio of games in which 2600 players defeat 2700 players.

Not at all. The longer the tournament lasts the better the chances that the strongest player will win it (the highest rated player and the strongest player are not always the same, of course). Statistically it's the only thing that makes sense; as the number of games increases the results tend to become more accurate reflections of strength.

Not quite. The longer the tournament lasts, the better the chances that the highest rated player will have the highest performance rating. But the longer the tournament lasts, the better the chances that the person with the highest performance rating will NOT be the winner of the tournament.

Of course, this trend is only true up to a point, because there are a limited amount of players. As you pointed out, with very long tournaments the top players will soon all be playing the same opponents and the tournament will be closer to a round-robin (a much better gauge of ability). But at 13 rounds (with this tournament size), this phenomenon is not enough to reverse the increase in difficulty posed to players who do well. A 19-round tournament might do the trick, but this is of course impractical.

Players who do well are generally going to face increasing difficulty. That's the way it should be. Thirteen rounds would have made a significant difference...

Examine what happened. Let's assume for the sake of argument that Tkachiev was *not* the best classical player at the tournament, even though I think most would agree (even before the playoffs) that he was the best rapid player.

In the main tournament Tkachiev had five full points, four were OTB wins and one was because his opponent forfeited. Each of the players he defeated was rated in the 2400s-2500s. This was at least a slightly less arduous road than, say, Jakovenko's or Pavasovic'.

With two more rounds Tkachiev would have had to play to more tough opponents, guys like Sutovsky or Jakovenko or Cheparinov or Sakaev. It's clear that with two more rounds the stronger players would have more time to establish themselves. Of course I would agree that Tkachiev was one of the strongest classical players in the tournament, but I don't believe he was *the* strongest. Two more rounds would have reduced the likelihood of multiple-ties and increased the likelihood that the winner would be the strongest classical chess player.

<<The longer the tournament lasts the better the chances that the strongest player will win it.>

Not quite.>

But Sutovsky, Jakovenko, Cheparinov, and Sakaev will also have to play more tough opponents. The people who do not are the people half a point behind. While it is very difficult for any of the leaders to get more than a half-point, probability says that at least a few of the 2550s in the 7.5 slot will beat another 2550 and vault themselves into joint first. The same thing will happen with the 8.0s in round 13, and so forth.

<It is a matter of sheer statistics. It doesn't make any sense to contend that the strongest player would be more likely to win an 11 round Swiss than a 13 round Swiss but less likely to win 11 rounds than 19 rounds. As the number of games increases that data increases and as the data increases the results become, statistically, more accurate reflections of relative strength.>

Again, you are confusing strength of play (think performance rating) with number of points. The two do not go hand in hand in Swiss events. To shed some light on this difference, say a near-infinite number of chess players played in a near-infinitely long Swiss tournament with no rules about playing the same person twice. After the initial place-sorting between stronger and weaker players, every single player would play every single game against someone with the exact same demonstrated strength. Therefore EVERYONE'S expected score is 50%. Of course the strong will have slightly higher scores (1.001 trillion vs trillion, for example) than the weak players, because of the initial place-sorting of the earlier rounds. But while the stronger players will continue to prove better in terms of ELO, they will not gain any tournament points on the weak players after the first few billion rounds.

In an actual tournament, the strongest players are playing each other by round 7 or so (depending on the size). As in any tournament, the strongest DOES have the highest probability of winning. (I never disagreed with this.) But in a deep tournament such as the European Championships, this probability is no higher with 13 rounds than 11. The guys who are "almost as strong" will continually be slightly behind or equal to the leaders in terms of tournament score, and some will always be winning against slightly weaker players to jump into the lead spots. No matter how long the tournament, it will always come down to the last round.

This continues until enough games have been played that the "best" stop playing the other "best" because they have already played them all. At this point, adding rounds begins to have a purpose again. Yes, it was dumb of me to arbitrarily say this happens at round 19--I have no idea when it starts (probably later than that). But the fact is adding rounds does have different effects on the tournament depending on the amount of participants and amounts of rounds already in place.

http://www.echecs.asso.fr/ (you have to search around. the exact link doesn't work)

1. Tkachiev 25.5/32
2. Fressinet 24.5/32
3. Karpov 24.0/32