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BGonline.org Forums
Stick, do you have 43U43 rolled out?
Posted By: Marty Storer In Response To: Stick, do you have 43U43 rolled out? (Chuck Bower)
Date: Friday, 29 August 2008, at 9:13 a.m.
First: Re 43 reply to opening 43: two up. You ask, in essence, whether a hit-and-split is a catch-up play. Splitting tries for an advanced anchor (the catch-up aspect), but it also increases racing chances, and it increases hitting chances on opponent's side of the board by controlling more territory.
To paraphrase what you asked, "If opponent anchors, isn't the split catch-up?" I would say it's partly catch-up, but it's more than that because when opponent makes an early advanced anchor (20, 21, 18 in particular), it becomes urgent to mobilize the back checkers to counter. That's because it's hard to block an advanced anchor, and impossible to attack anchored checkers. So if you knew opponent was going to anchor, you would love to start your next turn with split back checkers, because you'd want to split soon anyway.
As for 13/9 8/5*, there are so many ways to hit or anchor that I think a split is a better use of the 4 than coming down. Whether 8/4* 24/21 is better than 24/20 8/5*, I'm not sure, but I'm inclined to think so. Now I'll see what Stick says about rollouts etc.
Second: Re 63 reply to opening 43: two up. I said that plays other than 13/4* Really Stink [TM], but didn't elaborate.
I can go through them.
(1) 24/15 is much worse than usual because it's so unlikely to succeed as a running attempt: blot is 5/36 more likely to be hit immediately than after opening 63: 24/15, and it's less likely to reach safety next turn. So it stinks.
(2) How about 13/7 8/5*? That gives many more shots than 13/4*, leaves two blots instead of one, and strips the 8 point, merely in return to hit opponent off a more valuable anchor-point. Let's reject that one.
(3) How about 24/18 8/5*? The return 6's make it quite wide-open, especially given the stripped 8 point, as well as opponent's chance to anchor on the 21 with missing numbers; note that every reply but 66 hits somewhere, or anchors (I would hit with 33). So we can say that 24/18 8/5* stinks too.
(4) 24/18 6/3 is passive, giving opponent the initiative. The inside blot doesn't help, making it more difficult to hit back on the 18 point (combination shot needed), as well as inside (return hits on non-doubles leave two blots in the board).
(5) 13/7 24/21 is also passive and doesn't stand to gain much, though it's not too wide-open given opponent's lack of development. But I think that after 13/7, a better 3 than 24/21 has to be 7/4*. It reduces return shots and gives opponent some bad replies.
(6) 24/18 24/21 is just too passive, leaving opponent targets on points he'd like to make, totally giving up the initiative.
Thus some of the stinky 63-reply plays are clearly worse than 13/4*, and the others are at least quite arguably worse (clearly worse to me). Remember that you won't be able to prove they're all worse to a class of beginners; you just want to help them evaluate similar positions. Part of that is abstracting the right similarities to show what apparently quite different positions have in common.
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