Niemeyer

The idea is that opener (almost) always plays, but responder is leader of the auction. It will set the right contract (game) in 95% of all cases.

General approach: Transfers, and 3C as asking for 4 or 5 card majors.

I hope this in ACBL-allowed. It has lots of alerts (I think all calls of responder are alertable, and most of the other calls) but it's not that difficult to remember.

3C See below (That's the major part)

3D Transfer to hearts

3H Transfer to Spades

3S Transfer to Clubs (slam interest)

3NT shows 5 Spades + 4 Hearts. NON FORCING

4H To play

4S To play

4C Transfer to Diamonds (slam interest)

4D shows 5H + 5S. Opener places contract (1)

4H (I forgot)

4S Ace asking bid

4NT 6NT-try

5NT 7NT-try

3C Asks for 4 or 5 card Major

The only problems are the 5422 hands, with 5-4 Major or 5-4 Minor. 5-4 Major: there is no way to indicate this: the 4-4 fit will be missed. Solution: either open 2C (GF) or 1H/S. 2-2 Major: You'll have problems when pd shows 5-5 with 4D. But it's not that bad.