Again, to revisit the same topic (i.e. reaching winning position and losing due to blunders - how to avoid that?), just in case someone is interested:
1. Blitz - still suck at it. Hopelessly :) Not my format maybe? Maybe I am just a sloooooow loser ? :-)
2. Online and slow game training.
2.a i still keep playing correspondence chess, i think it helps somewhat with the positional understanding of the situation on the board and helps to learn those openings. still, blind following game explorer suggestions is annoying and useless.
2.b. I had several nice OTB sessions with a very good player (2300+ FIDE rating). Although not too pleasant (being consistently beaten), those were instructive.
3. Full tree tactics calculation? Well, i do have the tunnel vision of an amateur and keep missing simple moves. Or, I simply misevaluate the final position even if I do calculate correctly.
Again, despite reaching 2300-2400 rating on Tactics Trainer here on the site, i believe tactics is still the weakest link in my play (at my general level of ability).
4. I have learned a way of spoiling my mood for the evening: analyze my own game!!
I initially hoped I would discover several key "weaknesses" in my play and could work on correcting them. Well, after reviewing and annotating i started believing my game is nothing but weaknesses. It is frustrating just to sit there, looking at the board and saying : " just how come i made a move as stupid as this. unbelievable!"
5. Silman's ending book has started earning its points for me :-). Managed to nicely win some equal material/winning position endgames although 90% of my games are still decided in the middlegame
6. Almost completely ceased playing against the computer. Better study, review games or play online against people (10 min 15sec increment games). Much more enjoyable and better learning experience.
Conclusion?
a) I understood the value of coaching and mentoring. Playing against or looking over my game with a strong player was invaluable.
b) stopped being nervous about losses in blitz. yes, stupid moves, stupid losses, whatever. with my level of ability and availability for chess i need to have fun and stop being overambitious.
To revisit this issue in a bit over a year since I last wrote the comment.
Seeing tactics as the main problem, I did a lot of tactical exercises. On this site alone I have 7710 attempts. Less on other sites, but I am pretty sure 10 000 problems is a correct result for this year.
I also did some game reviewing, especially the old-timers (sac sac and mate - or resign - kind of games).
I did read the Novice Nook columns that Clavius (THANKS!) recommended.
I did play a lot of correspondence chess.
Results?
1. Well, i still suck at blitz :( Big time!
My current rating in blitz hardly ever reaches above 1500 and I consistently lose games to 1500+ players.
2. In online games I seem to be able to weed out most of the idiotic moves plaqueing my game in blitz. I am rated 2000+, have won a nice game against a titled player and otherwise am doing OK (despite having a few games like this one http://www.chess.com/echess/game.html?id=16923496 in my experience). I am much less confident about my positional ability, however :)
3. I think I have the "alarm bell" at last; however, i find it most difficult to calculate the full tree as NM ozzie_c_cobblepot suggested; i still think there is a lot that is based on intuition, especially for long (meaning 6-8 move) tactics. Maybe I started playing chess too late... Consequently, I sometimes miss a simple defensive move that ruins the whole idea of the combination.
4. Endgame ability has become much more important (especially for online games), however, i still lose pieces to simple 3-4 move tactics. Therefore, engame study is limited to basic king-and-pawn endagmes.
5. What i surely did wrong, was to play too many games against a computer. Those are most tiring games ever and I think they destroy my self confidence; the ease with which my attepts are refuted is disheartening.
Conclusion?
Should have started playing 20 years earlier