Round 13 - Playoffs 5 of 2016 US Tak Open

This past week saw a number more exciting games. SultanPepper and Unsweet have successfully locked themselves into the top 3 for this playoff.  Trailing behind them are other playtak veterans: Simon, Abyss, NohatCoder, Turing, Ally, and Simmon. Personally, I'm particularly interested in watching the upcoming match between Turing and Simmon.

As a bit of a prelude to this, the game I'm focusing on this week is the second in the match between Turing and Tayacan. This week, I wrote a brief, high-level annotation of the game that can be found at https://goo.gl/1co2QM or in the viewer below:

Round 12 - Playoffs 4 of 2016 US Tak Open

Having reached the end of round four, we begin the last 8 matches of the season. As a result, tensions are rising and any mistake can spell the last and make or break players.

In following this week's hubbub, I found myself particularly intrigued by the first game between ira212 and Abyss:

In particular, I spent a decent bit of time considering the position of the board after the white's 11th move:

[11. c4]

There's quite a lot I would have personally preferred to play for the opening lines, but this play creates an interesting setup for the board. A quick glance shows that black is slightly ahead - at least in terms of flat count and tempo. On the other hand, white has better control over the center, a stronger capstone, and more opportunities to develop road threats. The question for me, then, is which is more valuable - black's tempo or white's position?

If black chose to press tempo with f5' then white is forced to respond to the tak threat. There are four major lines here to consider: f6, e5-, d1>, and f1<, as shown in the corresponding image below:

{f6 / e5- / d1>  / f1< }

Of these, the best option is easily f6. For one - it maintains the flat differential. Secondly - it prevents breaking up the current structures. Finally - even if black were to follow up with e6', then white can respond with f6-, stopping any real immediate tak threat in its tracks:

[{12. f6 e6' 13. f6-}] 

At the end of this, it doesn't seem like black has gained much. Black no longer has tempo, his pieces are disconnected, and doesn't even have any real good control over white's area. That being said, with black at the helm, he can now interfere with whites center control. In the original game, Abyss played c5 to contest white's control. My initial reaction was to play b4, expecting white to respond with c5':

[{13. ... b3 14. c6'}]

Note how despite black's ability to hinder white's progress, white is definitely in control here. Black's earlier procedure leaving a flat on e6 doesn't even help his position. In contrast, White has a lot more flexibility.  Regardless of black's response, white has a lot of good options: d5- --> b3; b4>c3+ --> d4<; c6 --> b6'.

This in stark contrast to the types of maneuvers seen in the 5x5 games. In those games, these sorts of tak and tempo would have easily been able to turn the tide, putting white on the defensive. Instead, with the extended time on the 6x6, the positional advantage wins out.

Note, though, that the power of white's last move - c6' isn't simply the tak threat. That's some of the pressure. More so, white is strongly increasing position across the board and vying for control over the northwest corner. The tak threat only really limits black's responses and prevents black from gaining more ground. 

For the sake of 'completion', I also played this out with 13. ... c5 - closer to Abyss's original play. Following this line, I would actually play 14. b5 as white. In the original playthrough, (14. b4), black is able to close white off from reaching ranks 5 or 6. By extending now, and connecting diagonally to a current stone, white is able to extend control onto rank 5 - aiming to a north-south road potential. (and still having some good west-east potential)

[{13. ... c5 14. b5}]

Here too, white has a much better position and more flexibility to build towards future tak threats. Overall, these lines reinforce the importance of position in the 6x6 game - especially the value of the central squares.

Let me know what you think. Does white's position put him in the lead? How would you play this position out from either side?