The ambiguous response 2 Diamonds as response to opening 1 major

Opening 1NT with 5 cards in major and with 15-17H and balanced hand, is not a good idea. Much better is to open 1 or 1 and to use the ambiguous response 2 which brings more other benefits.

After opening 1 or 1, the ambiguous response 2 presumes a fit in major but with a weak and flathand of 5-7HCP, limit of Pass. After this response 2 the opener must always complete in major to 2 or 2, except if he has at least 18HCP. This response 2 is a complement of classical fitted responses such as, for instance after opening 1 :

2 (with 8HCP or 9-10HSP) *
3 (with 4 and 11HSP **)
2NT (with 3 and 11HSP **)
4/4 (splinter) with 4 and 11HSP and singleton /
4 (competitive) weak but with 5
2 (Drury) when the opener has opened in 3th or 4th position

* Justifies a safe trial bid by opener if he has at least 15H
** High Support Points

Of course, bidding the response 2 rather than 2 or 2 depends also on distribution. For instance if the responder has 7HCP, 3 cards in the five-cards major suiter and a singleton, he will make a direct support bid 2 or 2 instead of 2.

But this answer 2 is not always fitted in major, neither weak nor artificial. If the responder makes a second bid after 2 or 2, his first answer 2 is classical and natural with at least 5 and 11HCP and may be fitted in opener's major.

NB : If the opener has 5 4 he opens 1 then, after response 2, he bids 2 instead of 2
As response to 2, if the responder has a weak hand he passes with 4 and 3, but bids 2 with 3 without 4.

Main profits of this response 2 Diamonds

It enables to limit the contract to 2 or 2 if the responder is very weak, by dissuading the opener from bidding an unuseful and dangerous interrogative bidding 2NT or 3x when he has 15-17HCP.
It makes useless to open 1NT with a balanced hand of 15-17HCP with 5 cards in major : By opening 1 or 1, and whatever is his strenght, the opener is absolutely certain to find a fit 53 or 54 in his major if it exists. Therefore, why open 1NT with risk to miss an optimal fitted contract ?
Better than Pass with fit in major and 5-6HCP, the response 2 is competitive, mainly whan the trump is : If each line has about 20HCP, why let the opponent play quietly a contract at level 2. And mainly when no vulnerable.

Case of overcall by Double or by 2

We suggest using also this ambiguous answer 2 but only when opening has been made in 1° or 2° position

Case of opening 1 or 1 after 2 or 3 Pass

Never use this ambiguous answer after your Pass when opening has been made in 3° or 4° position, it would be dangerous : The opener may have only 10-11HCP. But you may or must use 2 Drury.

NB : This ambiguous answer 2 is also named Zanzibar

If not yet done, we suggest strongly reading Digest of precised major

contact : maubird@orange.fr