Made 5: E/W +650
and 16 IMPs to Jack

Even after HA lead almost any defense (trump or ♦Q return or duck of ♣K) will hold declarer to 9 tricks.  The contract should be defeated except for the actual play of the continuation of ♣J won by East's ♣K at trick two.

At table 1, Jack (N) had room to make a limit bid and Jack (S) was aggressive in jumping to 4♠.  With five trumps WBridge5 (W) ventured a double and kept WBridge5 (East) from saving in 5H.  At Table 2, Jack's (W) preempt kept WBridge5 (N) from showing a better hand.  Jack (E) bid 4♥ and then 5♥ on distribution, not giving Jack (W) a chance to double.  While the timing of the bids had some random influence at both tables, Jack clearly made better bidding decisions especially considering the vulnerability, and was rewarded with 16 IMPs.

The probability of making 6♠ is 37.4% (50% of the 67.8% of the times trumps are 3-2, plus 12.5% of the 28.3% of the times trumps are 4-1; plus none of the 3.9% of the times trumps are 5-0.).  The so called "rub of the green" in bridge!  A long match can be decided by one slightly lucky deal.  Of course, the luck tends to balance out and without a complete analysis it can't be determined which side had the better of it.

The last board of the match shows an interesting inference that humans sometimes get right and sometimes get wrong but robots always get wrong.

The play often depends on declarer's estimate of the level of an opponent's play.  Robots don't make such a judgment.

Final Q4 Board 16

Table 1

N/S: WBridge5   E/W: Jack

Opening lead ♥K, Made 5: N/S +450

Table 2

N/S: Jack   E/W: WBridge5

Down 1: E/W +50
and 11 IMPs to WBridge5

The play comes down to finding the ♣10.  The holdings that matter to declarer are West holding ♣ K, ♣ K 10, K x and K x x x.  With ♣ K x x, West will always duck the king and defeat the game.  With K x x x, West will never cover with the king as the 10 will show up.  With K 10, West will always cover.  With K x?  If it is known that West always covers with K x declarer will always get K x x x right (when the king doesn't appear play for the K x x x as opposed to K x) and have a guess for K 10, K x when it does appear, with the finesse of the 10 four times as likely as the drop of the 10.  If it is known that West never covers with K x then declarer will always get K 10 right (except for singleton king) and have a guess for K x and K x x x when the king doesn't appear.  If defender assumes, from K x, that if covering with the king, the declarer will always finessing for the 10, then defender will never cover from K x.  If declarer knows this is defender's tendency, then declarer will always get K 10 right (again, except for the singleton king)!  A matter of game theory (judging your opponent's tendency and with what probability) which the robots don't do!  The robots will always finesse for the 10 when the king is played and sometimes play the K from K x if only using double dummy techniques as double dummy either card loses (it is assumed that declarer will never go wrong).  In human play, with two known experts against each other, duck from K x most of the time (Edgar Kaplan would give the percentage quite accurately (80% of the time?)...as he did in his famous "The Deep Nine" article (The Bridge World, October 1973).

An excellent grand was bid and made at both tables.

Final Q3 Board 11

Table 1

N/S: Jack   E/W: WBridge5

¹singelton or void; ² 1 or 4 key cards; ³ one king

Table 2

N/S: WBridge5   E/W: Jack

¹ one key card; ² trump queen and club king (one king, not a heart)

Made 7 at both tables, E/W +1510, no swing

Final Q4 Board 3

Table 1

Making 12 tricks, E/W +1430

Table 2

opening lead ♦7

down 3, E/W -300

17 IMPs to Jack