Regarding a) it seems the strong bots can actually make some of the same blunders from blindspots as humans. Here's a human amateur dan game I was reviewing with Lizzie recently. When I saw white play the attacking/checking extension of 1 I thought "Oh, not c2?" Whether this was necessary for life or just a big reverse sente I didn't know without reading. So black played there and then came out.
$$Wc
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . O . . . . . |
$$ | . . . O . . . . . . . . X O . O O O . |
$$ | . . . , . . . . . X . . . . X X X O . |
$$ | . . O . . . . . . . . . X . . . X X . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . . 7 9 . . . . . . . . . . . . . . |
$$ | . . 1 6 . . . . . . . . . . . . . . . |
$$ | . . . 8 . 0 . . . . . . . . . . X . . |
$$ | . . X , . . . . . , . . . . . , . . . |
$$ | . X X O . . . . . . . . . . . . . . . |
$$ | X O X O . O O . . . . . . . . . . . . |
$$ | . O X X X X O . . . . . . . . . . . . |
$$ | . O O X X O O X . . . . . . . . . . . |
$$ | . . O X O . O . . . . . . . . . . . . |
$$ | . . O X X O . . . , . . . . . , X . . |
$$ | . . O O X . O . . O . X . . X . . . . |
$$ | 5 3 2 X . . . . . . . . . . . . . . . |
$$ | . 4 . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------
- Click Here To Show Diagram Code
[go]$$Wc
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . O . . . . . |
$$ | . . . O . . . . . . . . X O . O O O . |
$$ | . . . , . . . . . X . . . . X X X O . |
$$ | . . O . . . . . . . . . X . . . X X . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . . 7 9 . . . . . . . . . . . . . . |
$$ | . . 1 6 . . . . . . . . . . . . . . . |
$$ | . . . 8 . 0 . . . . . . . . . . X . . |
$$ | . . X , . . . . . , . . . . . , . . . |
$$ | . X X O . . . . . . . . . . . . . . . |
$$ | X O X O . O O . . . . . . . . . . . . |
$$ | . O X X X X O . . . . . . . . . . . . |
$$ | . O O X X O O X . . . . . . . . . . . |
$$ | . . O X O . O . . . . . . . . . . . . |
$$ | . . O X X O . . . , . . . . . , X . . |
$$ | . . O O X . O . . O . X . . X . . . . |
$$ | 5 3 2 X . . . . . . . . . . . . . . . |
$$ | . 4 . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]
White reduced on the right, and black made a placement inside the group. Boom! With the cut of 6 white was dead as short of liberties to make the 2nd eye if
a-b (so white played
b and made a ko to save some of the group).
$$Wc
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . O . . . . . |
$$ | . . . O . . . . . . . . X O . O O O . |
$$ | . . . , . . . . . X . . . . X X X O . |
$$ | . . O . . . . . . . . . X . . . X X . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . . O O . . . . . . . . . . . . . . |
$$ | . . O X . . . . . . . . . . . . . . . |
$$ | . . . X . X . . . . . . . . . . X . . |
$$ | . . X , . . . . . , . . . . . 1 2 . . |
$$ | . X X O . . . . . . . . . . . . . . . |
$$ | X O X O . O O . . . . . . . . 3 . . . |
$$ | b O X X X X O . . . . . . . . . . . . |
$$ | . O O X X O O X . . . . . . . . . . . |
$$ | . a O X O . O . . . . . . . . . . . . |
$$ | 5 4 O X X O . . . , . . . . . , X . . |
$$ | . 6 O O X . O . . O . X . . X . . . . |
$$ | O O X X . . . . . . . . . . . . . . . |
$$ | . X . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------
- Click Here To Show Diagram Code
[go]$$Wc
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . O . . . . . |
$$ | . . . O . . . . . . . . X O . O O O . |
$$ | . . . , . . . . . X . . . . X X X O . |
$$ | . . O . . . . . . . . . X . . . X X . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . . O O . . . . . . . . . . . . . . |
$$ | . . O X . . . . . . . . . . . . . . . |
$$ | . . . X . X . . . . . . . . . . X . . |
$$ | . . X , . . . . . , . . . . . 1 2 . . |
$$ | . X X O . . . . . . . . . . . . . . . |
$$ | X O X O . O O . . . . . . . . 3 . . . |
$$ | b O X X X X O . . . . . . . . . . . . |
$$ | . O O X X O O X . . . . . . . . . . . |
$$ | . a O X O . O . . . . . . . . . . . . |
$$ | 5 4 O X X O . . . , . . . . . , X . . |
$$ | . 6 O O X . O . . O . X . . X . . . . |
$$ | O O X X . . . . . . . . . . . . . . . |
$$ | . X . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]
So what does LeelaElf (the Facebook Elf OpenGo network converted to LeelaZero format) think in this tsumego? It doesn't see the cut, and just wants to play a ko (the only other moves it considers a small amount are on right side). I suspect this is because it's not seeing that the white group has no external liberties and is just looking at the local corner shape (in which the atari for ko is the best move if the white group has an external liberty). I've seen
other instances of bots playing local shapes like this ignoring the lack of liberties on large outside chains. However, once I play the black cut and evaluate again, Elf rapidly recognises that white is bad with a 30+ swing in win rate. Also, just to make sure Elf wasn't thinking as black it didn't like white making the ko 1st line connection, I added an exchange there so white was totally dead with the cut and it still wanted to play the ko mistake.

- ElfDumb.PNG (268.96 KiB) Viewed 13901 times
LeelaZero (#145) has the same blindspot (after 3k playouts). Maybe it or Elf would find the cut with more playouts?
How about regular Leela 0.11? It starts off liking the a5 atari, but b3 is a distant 3rd/2nd choice at least considered with <1% of playouts. Doesn't find it after 0.6m sims.
Would poor old maligned GnuGo get it right? I don't have it to check, but think it might.
How about humans? Well, here is Frank Jansen former 6d also missing the shortage of liberties to give the British player a valuable win in the Pandanet league this season (in fact he also missed that capturing the outside stone effects the life of the outside group so I think it becomes a seki instead of dead, but he resigned):
P.S. In the first game the white player was suspected of using a bot in another game, so does him missing the shortage of liberties suggest he was doing so here? Yes (a little bit), if we take it as given that human mid-high dans won't make that mistake. However, Frank is a nice counterexample that they do (he would have avoided this situation by playing hanging not solid connection some moves earlier). I am also aware that missing shortage of liberty situations is a common cause of my mistakes in tsumego problems.