[thorvald]

From the first challenge of today

You get this hand

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And you have to find an opening bid.

Opening 1♣ looks OK (That is what the bot would have done), but with a singleton Ace it is OK to treat this as a balanced hand, so opening 2N showing 20-21 could also be fine,

I decided to treat it as balanced, but with the many controls I upgraded it to 22, so i opened 2♣ and the bidding continued:

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I assumed that any double from the strong hand would be penalty, and was not sure if pass was forcing, but decided to pass to see what happened,

Note that 4N is defined to 28-30 HCP, just as without the 4♠ bid. I think that cheapest NT should show 22+ balanced with a stopper

The North bot did not find any bid, so EW played 4♠, 1 down.

Now that is not the interesting part of this deal, but more the replay of the board.

My opponent decided to show it as a 20-21 NT, so the bidding was

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5♣ went 2 down, but the interesting part is the explanation of 4N: Blackwood (D) -- 2-5 ♣; 5-♦; 2-5♥; 2-5♠; 21- HCP; rebiddable ♦; 26+ total points; two stops in ♦

Now on the actual hand 4N was an error, but it seems that after a transfer and then a bid from oppenents the Bot forgets about the transfer and assume the bid was natural

When testing this deal with the Bot as opener I also noticed, that East after a 1♣-opening, no longer would bid 4♠ if North passes (It probably assumes 4♠ is a fine sacrifice after a 2N/2♣-opening)

[EarlPurple]

Yes you might want 4NT to play, always difficult when opponent pre-empts but after a limit bid and a transfer that doesn't show any specific strength I'm highly unlikely to launch into Blackwood. You seemed to do well to end up defending.

Your opponent robot managed to find a good pre-empt on an 8 card suit, unlike my partner robots who always seem to suppress their suits. I ended up in a 3-3 fit when I guessed partner had long clubs, but he still should have corrected me back to my suit.