opportunities for encryption in bridge

[gnasher]

Or even, the key is based on the parity of the first pip played from dummy on this board. Lots of people will have difficulty remembering this.

I remember playing against a pair who did this. They'd got through two days of the Brighton Teams without getting into trouble.

[hrothgar]

Is this legal?  Should it be legal?  [Obviously it won't work more than once.]

My guess is that it would be illegal to use a key from the previous board, but probably legal to use a key from the current board.

 

At least, that is how I think it should be. If the key is not related to the current board, you must say what carding you are playing. Even though the first board was played against the same opps, it should be considered external information. Like saying that our carding depends on whether the 357th decimal in pi is odd or even.

I concur with Helene's line of reasoning

I also believe that this is consistent with the Laws

[rbforster]

Or even, the key is based on the parity of the first pip played from dummy on this board. Lots of people will have difficulty remembering this.

Or for more fun, let the carding key be based on the parity of the first pip played by 3rd hand on the first trick. This way you can figure out if you want to play UDCA or standard for this hand and choose your pip accordingly :P.

[akhare]

Is this legal?  Should it be legal?  [Obviously it won't work more than once.]

My guess is that it would be illegal to use a key from the previous board, but probably legal to use a key from the current board.

 

At least, that is how I think it should be. If the key is not related to the current board, you must say what carding you are playing. Even though the first board was played against the same opps, it should be considered external information. Like saying that our carding depends on whether the 357th decimal in pi is odd or even.

Another way of looking at it is that the pair likes to randomly switch between udca / standard and the last pip played, nth digit of pi modulo board number, etc. are just being used as source of entropy.

 

As such, I have no objections to such methods as long as they are willing to disclose the current state if queried. A prudent declarer would be well advised to ask third hand before playing from dummy at T1.

 

However, they might run afoul of regulations that require stipulatation of carding on the convention card -- however, I guess you can always tick both the udca / standard boxes ;).

[rbforster]

Here's a simple way to add an encryption attempt early in your strong club relays. After any positive response, for example a transfer positive:

 

1♣*-1♥* strong; showing spades

 

now opener uses his first and second steps as relays showing if he holds exactly one of the AK in partner's suit. So

 

1♣-1♥-1♠ relay, shows 1 of the AK♠ by opener (attempted key exchange)

1♣-1♥-1N relay, shows 0 or 2 of the AK♠ by opener (continue with unencrypted relays)

 

If opener shows 0 or 2, relays proceed unencrypted with responses of 2♣+, having lost one step of bidding space in the attempt. If opener shows 1, responder bids the cheapest step (1N) to confirm the encryption or bids 2♣+ as before to deny a high honor and without encryption.

 

1♣-1♥

1♠*-2♣+ showing 1 of AK♠; unencrypted relays denying the other

 

1♣-1♥

1♠*-1N* showing 1 of AK♠; confirming the other

2♣-... encrypted relays proceed with 2♦ and higher responses

 

So when you fail to get a key, you have lost 1 step for trying (2♣+ relay responses instead of 1N+). When you get a key, you'll have lost 2 steps (start relays with 2♦+). Note that if you are going to eventually ask for honors in partner's primary suit, such as with denial cue bids, you will be able to skip this step and regain the "lost" space on those auctions.

 

Since this is a simple modification that anyone can make to their favorite strong club system and since it preserves the normal suit-showing first responses (in case of interference), it seems like this would be a fun thing to test to see if the encryption helps.