kenrexford, on 2014-March-07, 12:35, said:
Weal two's are allowed because they are not conventions, the same as 1 level opening bids.
The new GCC references the Alert Pamphlet Definitions for definitions. I think it should have referenced definitions in the Alert Chart which are better written and comprehensive (IMO) which clearly state what is not a convention, ie.
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Treatment: A natural call that, by partnership agreement, carries a specific message about the suit bid or the general strength of the hand. Such bids are not conventions and therefore not regulated by the ACBL Convention Chart. Consult the ACBL Alert Chart for those treatments which require Alerts and/or Announcements. As to length ACBL accepts the following as treatments.
1. All bids listed above as natural.
2. A two-level suit opening, jump response and jump overcall that, by partnership agreement, guarantees five or more cards in the named suit.
3. A three-level suit opening, jump response and jump overcall that, by partnership agreement, guarantees six or more cards in the named suit.
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So, 2 level bids which guarantee 5 or more cards in the suit are ACBL approved treatments of natural bids, and not a convention.
The Alert Pamphlet doesn't make clear that 2 level bids with a 4 card suit are regulated by the GCC as a convention.