Mini Notrump
EHAA uses a ten to twelve notrump range; the distribution must be 4-3-3-3 or 4-4-3-2. On occasion, a 5-3-3-2 hand with a long minor can be opened 1NT if the values are concentrated in the short suits.
Opposite the mini notrump, there is no reason to use transfers or many of the other accoutrements of standard notrump systems. Accordingly, 2♦, 2♥, 2♠, and 3♣ are nonconstructive improvements of the contract. Holding minimal values and a five card suit, responder should take out 1NT almost automatically. Responder passes with no five card suit, or with enough values to make 1NT a likely possibility.
With five-five or better in the minors, responder bids 2NT, and opener rebids his better minor. Responder passes with a minimum, and raises for a game try.
Responder can also raise to 3NT, 4NT, 5NT, 6NT, and 7NT, with their standard meanings.
For game invitational hands, whether they have a four card major or not, responder bids 2♣ Stayman. Opener's rebids are standard, except with two four card majors opener rebids 2NT with a minimum and 3♣ with a maximum. (For this reason, responder cannot use "garbage Stayman".) After opener's rebids, a new suit by responder shows a five card suit; bids at the two level are invitational and bids at the three level are forcing to game.
All suit bids of 3♦ or higher are preemptive. It is this ability of responder to preempt with a six card suit and no values which makes the EHAA mini notrump itself a splendid preemptive bid.
If 1NT is doubled, some sort of escape system may be used. It is suggested that all two bids (even 2♣) are to be intended to play; redouble by responder is SOS. Some play that with a good hand, responder passes and opener must redouble, which responder will pass for penalties or take out showing invitational values or better (although this is not common).
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