Summary

Case 1 (2"transfer" followed by 3 )

Whilst this is a legal method, in our experience it tends to arise not by agreement but because either responder has forgotten that the pair are playing transfers or opener has forgotten that they are not playing transfers. Alternatively, responder may be inventing system at the table because he does not know what to do with a weak hand with diamonds.

In the original form of transfers, this sequence shows 5 hearts and 4 diamonds and is forcing for at least one round. If you wish to play transfers, we believe that it is much better to stick to this meaning for the sequence. There are a number of other sequences available for signing off in diamonds : for example, responses of 2,2, 2NT, 3 and 3can all be put to good use in one way or another (there are many different methods available on the market).

You should also note that if you do play the sequence as showing a weak takeout into diamonds, the 3rebid is alertable as well as the initial 2response, because it is non-forcing, whereas the normal meaning for the sequence is forcing.

Case 2 (2Stayman followed by 3)

This is relatively harmless, for three reasons. First, the original form of the Stayman convention caters for the possibility that 2 followed by 3 is a weakness take-out. Secondly, the opponents are probably aware (or, at least, they should be aware) of the possibility and can ask if they need to know (there are many different schemes of continuations after Stayman, and opponents should not assume that any one, rather than any other, is in use). Finally, it is not really credible to imagine that a player has forgotten whether or not he is playing Stayman, so the unauthorised information problems are unlikely to arise.

It would be refreshing to see convention cards made out, or explanations given, such as "2Stayman - could be the first move as a weakness take-out into clubs." However, it isn't absolutely essential to do so, because opponents are unlikely to be misled.

Case 3 (2Astro followed by 3 )

This is similar to case 1, but worse, for two reasons. First, because if you are playing at Level 2 it is not a permitted method. Second, because the unauthorised information problems tend to be worse because there is a much wider range of hands that a responder to an overcall might have, in comparison with a 1NT opener.

Our advice is that if you play Astro (or similar), then with a one-suiter in diamondsyou should agree to overcall 3 immediately (you're going to end up at the 3-level anyway, so why beat about the bush?).

Case 4 (2 Pinpoint Astro followed by 3)

This is similar to cases 1 and 3, but without the possible problems with permitted methods. Again, if you want to play a method whereby all two-level overcalls show two-suiters, you should agree to use some different call to show the one-suiters. A direct jump to the 3-level is the obvious choice, but at Levels 3 and 4 you can even use double to show an unspecified one-suiter - if (and of course it's a big "if") you are prepared to forego the use of a penalty double.

General advice

If you insist on using these two-way methods, then you should be careful to protect yourselves by:

• providing full details on your convention card;
• providing the opponents with a full explanation should they ask for one; and
• making sure that neither you nor your partner forget the system.