I've never been impressed with Silman either as a player or a coach, but he's got quite a reputation as a coach.

Jack Collins, who I believe coached Fischer when he was young, wasn't a particularly strong player either.

Weeramantry's stepson (Hikaru Nakamura), on the other hand, became a GM at 15+~2months, breaking Fischer's record as the youngest American to become a GM. Nakamura is also putting in a decent showing at Wijk aan Zee in the B group, but doesn't get kibitzed about, because he's no longer a novelty at the ripe old age of 16.

Originally from Sri Lanka, he came to the United States for the first time in August 1971, where he entered into a tournament for young players in New York. It was a marathon nine-round event over three days, with over 400 participants, at the McAlpine Hotel in Midtown Manhattan. Sunil astonished the other players by winning his first six games outright, including victories over two masters. He also became known for his engaging personality, easygoing demeanor, and fine sense of sportsmanship. By the end of the second day, it seemed that he had befriended almost all the leading players.

Then, incredibly, disaster struck on the third day when he lost two games in rapid succession. Possibly, he was simply tired. Going into the final round, four players were leading with 6.5, and Sunil was tied with several experts, all of whom had accumulated 6 points out of eight. The leading players all drew each other, so that a score of 7 points would have enabled Sunil to share first prize. Instead, facing a local expert and in serious time pressure, Sunil was in a hopelessly lost position by move 41.

Then he came up with an incredible combination. He sacrificed a rook and a queen, thereby stalemating himself. There was an audible gasp from the spectators, which rapidly escalated into a roar. His opponent was so stunned that he nearly fell out of his chair. One of the spectators asked the tournament director to publish the final position in Chess Life. Later, Bill Goichberg analyzed the game along with the opponent, and described it as “Wild – they were attacking and counterattacking each other all over the place.” It was one of the most inspired drawing combinations ever played.

several coaches were asked what an older player would need to do to become a strong player.

the coaches answers were hypothetheical at best , they seem to have no experence in seeing a mature player improve upto to the expert level.

It seems to me that, after you have played roughly 1000 games, you have gotten about as good as you are going to get. Yes, you may still be able to make small refinements to your play to add a few rating points here and there, but the days of quantum leaps are long gone.

http://tinyurl.com/59kyov

2004 Interview by Dr. Daaim Shabazz

2) I think de la maza proved you could get from 1600 to 2200 in about 2 years using the seven circles, so add to that exchange type openings that reduce the piece complexity & tension (Ruy Lopez exchange etc...and a good endgame. you should be able to get to 2200+

3)Advantage for the adult
-Can buy any chess software Chessbase 9 plus those repertoire books! -tactics software
-You have money for GM instruction on ICC

4) The computer has levelled the playing field now you have the whole world & computers to practice against

To add to your points about premaster to GM...Yury Shulman recently told me that while he was in college(!) in Belarus he improved from "about expert strength to 2550 level in three years." "Three years??" [Thinks about it]. "Hmm...I think like 2 years-plus." He did this by studying 12 hours a day, but it does suggest that such things are possible. He wasn't some 14-year-old GM or something.

The big issues in chess improvement are desire, time (to study and train and play), and money (to pay for it all). If you have those three things, a lot is possible. However, most adults do not have all three of those ingredients in sufficient quantity!

Give a motivated, hardworking adult a high-quality trainer (I'm not even saying Dvoretsky or someone of that ilk), give them 7 hours a day to train (the trainer will direct the student on what and how to train, of course), give them unlimited time to travel to play in tournaments, and give them unlimited funds to pay for it...I see no reason why they cannot become at least IM.