38. Rxa6 Rxa6 39. c7 Raa8 40. Rb8 Raxb8 41. cxb8=Q Rxb8 42. Nd7+ Ke7 43. Nxb8

which eventually wins but it's veeeeeerrryyy sloooooooooow:

<Once: <SufferingBruin> Enjoyed your post, as always. Very well written and funny.

If you stick with it, a funny thing will happen. You will get better. Problems that currently elude you will become ridiculousy easy. You will spot the key move much more quickly. Tactics and themes will suggest themselves. Some grandmasters talk about the move that the position demands - an instinctive pull to the right solution, or at least a very tempting one.>

My youngest Grandson was born in February 2009, and will be 10 years old this month. I taught him to play when he was four years old, and have helped coach him since then.

Much of what <RV> wrote about persistence and determination applies to my grandson's progress. He was a USA top 100 player as an 8-year-old, and this past year he improved over 200 rating points and is now a solid class C player.

In November, 2018, he beat a class A player and a class B player in a local city swiss tournament to score 4 out of 5 and tie for second place.

In January of this year, he took first place in the high school section of a tournament in Fort Worth, Texas with a perfect 5-0 score. Last week, he and his brother (age 13) and a friend (age 14) won the first place high school division team trophy in the Region 2 (28 county region including Fort Worth and Waco) Texas scholastic championship. In the regional championship, he scored 4.5 out of 6 (only one loss to a 1600 player) to take fifth place overall -- not bad for a 9-year-old competing against 15 to 17 year-old players.

<38.?>

For Thursday Valentine's Day 2019 we have a repeat of a <Saturday> puzzle from 2009... I commented on this game then (which I rarely did in the weekends), and I do think all that analysis holds up, so I won't bother myself with more of myself. Although, I did want to play slightly different moves than my own self:

1) I did intend the entire game line instead of 42.Nd7+?! in 2009: 42....Ke7 43.Rxa8 Kxd7 44.Rxg8 Kxc7 +-. It's not changing anything, the game line's just faster because White will promote instead of being a rook up.

2) However, after the 37....Rf8 defense I somehow settled on 38.Nd7+ Ke7 39.Nc5+?!, winning only the bishop, instead of 39.Nxf8+! in 2009 which forcefully wins the rook after 39....Kxf8 (otherwise the Knight's just there) 40.c7 Rc6 41.Rb8+ with c8=Q.

Human mind and its 'progress'. Weird.

How to look at this puzzle for chess progress in general though?

A Saturday ten years ago becoming a Thursday now, is this a trend where the current chess world simply calculates more, has more sources at their disposal to become better and be more adapt at tactical calculations?

Funny that many moves win here:

click for larger view

Stockfish_19020810_x64_modern: <16 minutes computer time>

<43/65 +8.85 38.Rxa6> Rxa6 39.Rb7 Rg7 40.c7 Ra8 41.Rb8 Rxc7 42.Rxa8 Rb7 43.Kh2 Ke7 44.Ra6 Rb1 45.a4 Rb3 46.a5 Ra3 47.Kg1 d4 48.Ra7+ Kd8 49.Nc6+ Kc8 50.Nxd4 Ra4

42/67 +8.24 38.R2b4 Bc8 39.a4 Rg7 40.Rb8 Rxb8 41.Rxb8 Rc7 42.Kf2 d4 43.Ra8 Ke7 44.Ke2 Kd6 45.Kd3 Kc5 46.Ra5+ Kb4 47.Rb5+ Kxa4 48.Rb2 Ba6+ 49.Kxd4 Bb5 50.Kc5 Bxc6

42/73 +8.20 38.a4 Rg7 39.a5 d4 40.Nd7+ Ke7 41.Nc5 Bc8 42.Rb7+ Kf6 43.Rxg7 Kxg7 44.Rb7+ Kf6 45.a6 e5 46.a7 d3 47.Nxd3 exf4 48.Rb8 Rxa7 49.Rxc8 Ke6 50.Rd8 Rc7

42/59 +7.40 38.c7 Bc8 39.Rd6 Rg7 40.Rc2 Ra7 41.Rd8 Rgxc7 42.Rxc8 Rxc8 43.Rxc8 Kg7 44.Rc2 Ra4 45.g3 Kf8 46.h4 Ke7 47.Rc8 Ra3 48.Kg2 d4 49.Rc2 h5 50.Rd2 Ra6

Stockfish 10 says:

38.Rxa6

(38. Rxa6 (♖b6xa6 ♖a8xa6 ♖b2-b7 ♖g8-g7 c6-c7 ♖a6-a8 ♖b7-b8 ♖g7xc7 ♖b8xa8 ♔f6-e7 ♖a8-a6 ♖c7-c1+ ♔g1-f2 ♖c1-a1 ♘e5-c6+ ♔e7-d7 ♘c6-d4 ♖a1-c1 ♖a6-a7+ ♔d7-c8 ♘d4xe6 ♔c8-b8 ♖a7-d7 ♖c1-c2+ ♔f2-g3 ♖c2xa2 ♖d7xd5 ♔b8-b7 ♖d5xf5 ♔b7-c6 ♘e6-d4+ ♔c6-d7 ♖f5-e5 ♖a2-a4 ♖e5-d5+ ♔d7-e7 ♘d4-f5+ ♔e7-f8 ♘f5xh6 ♖a4-a3+ ♔g3-h4 ♖a3-a6 ♘h6-f5 ♔f8-f7 ♘f5-d4 ♖a6-h6+ ♔h4-g3 ♖h6-g6+ ♖d5-g5 ♖g6-a6 ♖g5-f5+ ♔f7-g6) +7.83/35 )