Hello again,
I would like to show a "vice versa" example, a tactical blunder two very strong engines are making. It's from the a very rare win of OliThink (5.7.9, black) against Stockfish (11, white) on medium time controls:
[d]4rr1k/p2R2pp/3R2p1/q1p5/P1Q5/1P2B2P/5PP1/4b1K1 w - - 4 32
Stockfish/Ethereal think 32. Ra6 is best move, which is actually very big blunder. (33...Rxe3 wins the match for black). They are doing this until depth 21.
Other, "weaker/stranger" engines however refute this move immediately (e.g. Fruit, OliThink or Leela):
Here the analyze log of SF11:
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21 +3.51 1.87M 0:00.91 Qxc5 Qxc5 Bxc5 a5 Bd4 Rg8 Rc7 Rb8 Be5 Rbf8 f3 Bh4 Ra7 Bd8 Kh2 Bf6 Rxa5 Ra8 Rb5 Bxe5+ Rxe5 Rgb8 Rb5 Rxb5 axb5
20 +4.29 1.02M 0:00.54 Ra6 Qc3 Qxc3 Bxc3 Bxc5 Re1+ Kh2 Rc8 Rc6 Rg8 Rxa7 Rb1 Rb7 Ra8 g3 g5 Be3 Bf6 a5 h5 a6 g4 a7
19 +3.95 696243 0:00.38 Ra6 Qc3 Qxc3 Bxc3 Bxc5 Re1+ Kh2 Rc8 Rc6 Rg8 Rxa7 Rb1 Rb7 Ra1 g3 Be5 Kg2 Bf6 Be3 Be5 Rd7 Ra2 Bd2 Bf6
18 +3.75 610301 0:00.34 Ra6 Qc3 Qxc3 Bxc3 Bxc5 Re1+ Kh2 Rc8 Rc6 Rce8 Bxa7 Be5+ g3 Ra1 Be3 Ra3 b4 Rxa4 b5 Kg8 b6 Ra6 Ra7 Rxa7 bxa7
17 +3.90 350067 0:00.22 Ra6 Qc3 Qxc3 Bxc3 Bxc5 Re1+ Kh2 Rb8 b4 h5 Raxa7 Be5+ g3 h4 f4 Re2+ Kh1 Bb2 gxh4 Bf6 b5 Kh7 Rab7
16 +4.11 265230 0:00.17 Ra6 Qc3 Qxc3 Bxc3 Bxc5 Re1+ Kh2 Rc8 Raxa7 Rb1 b4 h5 a5 Be5+ g3 h4 f4 hxg3+ Kxg3 Rb3+ Kg4
15 +4.02 159797 0:00.10 Ra6 Qc3 Qxc3 Bxc3 Bxc5 Rf4 Raxa7 Rfe4 Be3 Rb4 Rdb7 h6 Rxb4 Bxb4 Rb7 Be7 a5 Kh7
14 +3.72 116612 0:00.08 Ra6 Qb4 Bxc5 Qxc4 bxc4 Rd8 Rxd8 Rxd8 Rxa7 Bc3 Bb6 Rf8 a5 Kg8
13 +3.61 97979 0:00.06 Ra6 Qc3 Qxc3 Bxc3 Bxc5 Rf5 Be3 h5 Rc7 Be5 Rcxa7 Kh7 b4
12 +3.44 50457 0:00.04 Qxc5 Qxc5 Bxc5 Rc8 Bxa7 Rc1 Rd1 Rxd1 Rxd1 Bc3 Bb6 Kg8 Kf1 Kf7 a5 Rc8
11 +3.44 30452 0:00.02 Qxc5 Qb4 Rd3 Rg8 Qxb4 Bxb4 Rxa7 Rc8
10 +3.08 23090 0:00.02 Qxc5 Qxc5 Bxc5 Re2 Rd1 Bxf2+ Kf1 Bxc5+ Kxe2 Rf2+ Ke1
9 +2.86 17639 0:00.01 Qxc5 Qxc5 Bxc5 Re2 Bxa7 Bxf2+ Bxf2 Rexf2 Rd8 Rf5 R6d7 Rf1+ Kh2
8 +3.14 10973 0:00.01 Qxc5 Qxc5 Bxc5 Bc3 Rd3 Re1+ Kh2 Be5+ g3
7 +3.28 3255 0:00.00 Ra6 Rxe3 fxe3 Qb4 Qxb4 Bf2+ Kh2 cxb4
6 +6.38 1349 0:00.00 Bxc5 Re5 Bd4 g5
5 +6.52 921 0:00.00 Bxc5 Rf5 Bxa7
4 +7.86 412 0:00.00 Ra6 Rxe3 Rxa5 Bxf2+ Kh2
3 +8.31 245 0:00.00 Ra6 g5 Rxa5 Bxa5 Qxc5
2 +4.21 134 0:00.00 Rc6 g5
1 +3.65 61 0:00.00 Bxc5
Ethereal 12.46 is having the same problems with this position as its analysis after move 32. a6 verifies a tactical blindness for Rxe3. This is a move, that many human player can see.
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23 +4.53! 5.67M 0:02.53 Rxe3!
23 +2.99! 5.64M 0:02.51 Rxe3!
22 +0.01 5.39M 0:02.40 Rxe3 Rxa5 Bxf2+ Kh1 Re1+ Kh2 Bg1+ Kh1 Be3+ Kh2 Bg1+
21 -4.21 3.83M 0:01.71 Qc3 Qxc3 Bxc3 Bxc5 Re1+ Kh2 Rc8 Rdxa7 h5 Ra8 Rg8 b4 h4 g3 hxg3+ Kxg3 Rg1+ Kh2 Rc1 Be3 Rb1 b5 Rxa8 Rxa8+ Kh7 b6
20 -4.21 1.42M 0:00.64 Qc3 Qxc3 Bxc3 Bxc5 Rf5 Be3 Rff8 Raxa7 Rb8 Rab7 Rfe8 Rdc7 Rxb7 Rxb7 Kg8 b4 Ra8 a5 Bxb4 Rxb4 Rxa5 Rb7 Ra2 g3 h5 Kg2 Kh7
19 -4.18 1.15M 0:00.52 Qc3 Qxc3 Bxc3 Bxc5 Re1+ Kh2 Rc8 Raxa7 h5 b4 Kh7 a5 g5 a6 Be5+ g3 Kg6 Rab7 g4 hxg4 hxg4 Kg2
18 -4.24 914315 0:00.42 Qc3 Qxc3 Bxc3 Bxc5 Rf5 Be3 Rff8 Raxa7 Rb8 Rab7 Rfe8 Rxb8 Rxb8 Bd4 Bxd4 Rxd4 Ra8 g3 Rb8 b4 Kg8
17 -4.26 737845 0:00.34 Qc3 Qxc3 Bxc3 Bxc5 Rf5 Be3 h5 Raxa7 Rb8 Rab7 Rxb7 Rxb7 Rd5 Kf1 Rd1+ Ke2 Rg1 Kd3 Be5 a5 Rxg2
16 -4.12 484827 0:00.24 Qc3 Qxc3 Bxc3 Bxc5 Rf5 Be3 h6 Raxa7 Rb8 Rab7 Rxb7 Rxb7 Ra5 Kf1 Kg8 Rc7 Be5 Rd7 Ra6 Ke2 Rc6
15 -3.65 314947 0:00.16 Qc3 Qxc3 Bxc3 Bxc5 Rf5 Be3 h6 Raxa7 Rb8 Rab7 Rxb7 Rxb7 Kg8 b4 Rf7 Rb8+ Rf8 Rxf8+ Kxf8 b5 Ke7
14 -3.60 197857 0:00.11 Qc3 Qxc3 Bxc3 Bxc5 Rf5 Re6 Rc8 Bxa7 h5 Be3 Kh7 Ree7 Rh8 b4 Rb8 Rb7 Bxb4 Rxg7+
13 -3.19 57050 0:00.03 Qc3 Bxc5 Qe5 Rf7 Rxf7 Qxf7 Bc3 Rxa7
12 -4.32 22607 0:00.01 Qc3 Bxc5 Qxc4 bxc4 Rf6 Rxf6 gxf6 Bd4 a6 Bxf6+ Kg8 c5 Ba5
11 -4.23 18981 0:00.01 Qc3 Bxc5 Qxc4 bxc4 Rf6 Raxa7 Rc6 Bd4 Rxc4 Bxg7+
10 -4.61 15997 0:00.01 Qc3 Bxc5 Qxc4 bxc4 Rg8 Raxa7 Bc3 Be7 Bf6
9 -4.07 2634 0:00.00 Qc3 Raxa7
8 -8.74 1355 0:00.00 Rd8 Rxa5 Rxd7 Rxc5
7 -9.61 939 0:00.00 Rd8 Rxa5 Rxd7 Qxc5 Rb8 Rxa7
6 -9.61 789 0:00.00 Rd8 Rxa5 Rxd7 Qxc5 Rb8 Rxa7
5 -8.95 451 0:00.00 Rd8 Rxa5 Rxd7 Rxc5 Rfd8
4 -8.74 265 0:00.00 Rd8 Rxa5 Rxd7 Rxc5
3 -9.62 121 0:00.00 Rf5 Rxa5 Bxa5 Rxa7
2 -10.00 45 0:00.00 Rg8 Rxa5 Bxa5 Qxc5
1 -10.00 29 0:00.00 Rg8 Rxa5 Bxa5 Qxc5
PS: There may be some kind of explanation: After 33...Rx3 34. Rxa5 white looks leading for an eternity, because black is check-chasing the king around the board without gaining material for a long time:
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39 #29 16.3M 0:05.00 Bxf2+ Kh1 Re1+ Kh2 Bg1+ Kg3 Re3+ Kg4 h5+ Kg5 Rg3+ Qg4 hxg4 Raxa7 gxh3+ Kh4 h2 Kxg3 h1=Q Rf7 Bh2+ Kf2 Qg1+ Ke2 Qxg2+ Ke3 Bg1+ Kd3 Rxf7 Rxf7 Qd5+ Kc3 Bd4+ Kc2 Qxf7 a5 Qe6 b4 Qc4+ Kd2 Qxb4+ Kd3 Qxa5 Kc4 Qa4+ Kd5 Qa6 Ke4 Qc4 Kf3 Q
It seems that SF/Ethereal do not fellow check sequences too deep. This may lead to a tactical blindness, but of course gains in overall strength as such positions are rare.