[pbleighton]

In another thread (ACOL, in the Partner section), hrothgar made mention of rules banning certain conventions.  I have been reading about a lot of artificial systems (new to me, and fascinating and promising), and are wondering which ones (and versions of others) fit under this definition, which I found on the web.  It appraently applies to Europe:

For the purpose of this Policy, a Highly Unusual Method (HUM) means any System that exhibits one or more of the following features, as a matter of partnership agreement:

a) A Pass in the opening position may have the values generally accepted for an opening bid of one, and the player who passes may hold values a queen or more above the strength of an average hand (an average hand contains 10 HCP)
By partnership agreement an opening bid at the one level may be weaker than pass.
c) By partnership agreement an opening bid at the one level may be made with values a king or more below average strength.
d) By partnership agreement an opening bid at the one level shows (a) either length or shortage in a specified suit or ( either length in one suit or length in another

Artificial: this category includes all artificial systems that do not fall under the definition of Highly Unusual Methods (HUM) systems [see definition below], other than Strong Club/Strong Diamond systems (see 'Blue').
Examples would be a system where one club shows one of three types - a natural club suit, a balanced hand of a specific range, or a Strong Club opener; or a system in which the basic methods (other than the no trump range) vary according to position, vulnerability and the like; or a system that uses conventional 'weak' or 'multi-meaning' bids (with or without some weak option) in potentially contestable auctions, other than those described in the main part of the WBF Convention Booklet


Are the ACBL regs pretty much the same?
Questions re U.S. practice, and where it varies from general world regs (I know that some countries are looser):
1) This means you can't Pass with an traditional opening hand, AND you also can't pass with a subopening hand, if there is a bid defined which is weaker than the subpopening hand you would like to pass with.
2) An opening bid at the one level can't be made with less than 8 hcp.  Does this include 1NT? Can you have a range of 8-12, and open it with  6 or 7 with a long/strong suit?
3) "either length or shortage in a specified suit" - does this mean for example 1 heart showing either of a) stiff or void in hearts, or 6+ hearts.  Is it OK to have 1 diamond show 5+ hearts?
4) What about subsequent bids - does using transfer positives in Precision cause it to be reclassfied as artificial or HUM, for example, or are relay bids so far safe from the regulatory grasp (I say this as a card-carrying liberal ).
5) What about a system such as:
1 diamond - 9-11 pts, bal
1 heart - 11-15 pts, 5+ hearts
1 spade- 11-15 pts, 5+ spade
1 NT - 15-17 bal
2 clubs - 11-15 pts, 6+ clubs
2 diamonds- 11-15 pts, 6+ diamonds
2 hearts and up - weak
1 club would then have the 16+ hands, and a ton of 11-15 hands.  Would this make it HUM, since it is more than "one of three types", and 1 diamond isn't about diamonds?
6) Would you give me an example of "a system that uses conventional 'weak' or 'multi-meaning' bids (with or without some weak option) in potentially contestable auctions", which would make a natural or Strong Club system into and Artificial system?
7) "By partnership agreement an opening bid at the one level shows (a) either length or shortage in a specified suit or ( either length in one suit or length in another" - does anything like this apply at the two level?
Is there a general rule about ambiguous bids at the two level - I've read that using 2D to show all 4441 shapes with sunopening hands is treated differently than if is 17-24 points.  Is this so?

8) Can artificial systems be played at the club level?

I know that this subject is huge, and that answers could be very long and involved, but I am looking for some general parameters.

[hrothgar]

The ACBL uses three different mechanisms to license Conventions.

The first is a set of Convention Charts that define the sets of conventions that are licensed for use at different levels.

The ACBL has four different levels of convention charts:

The Limited Convention Chart
The General Convention Chart
The Midchart
The Superchart

In addition to this, the ACBL has labeled certain conventions as inherently destructive.  These methods are banned at any level of play.

Over the last three years the ACBL introduced a highly annoying "back door" regulatory structure.  The ACBL Midchart is actually fairly reasonable with respect to the set of methods that it permits.  For example, the Midchart licenses any bid that promises 4+ cards in a known suit.  However, the ACBL Conventions Committee added a new requirement that any Midchart method needs to have an approved defense  submitted in the ACBL's defensive database.  

The Convention Committee has not been particularly helpful in adding defenses to the Defensive Database.  This requirement is being used to block players from using a wide variety of methods that aren't favored by certain members of the committee.

I should note at this time that Fred Gitelman is a member of the Conventions Committee.  I've always found him much more response and helpful than other members of the committee, though [obviously], I still have major issues surrounding the way in which the Conventions Committee is operating.

[pbleighton]

The Limited Convention Chart
The General Convention Chart
The Midchart
The Superchart


Do these translate to types of games/tournaments they are allowed in? Are Limited conventions allowed everywhere, and Superchart conventions allowed only at regionals and above for example (or vice versa)?

[hrothgar]

The ACBL devolved authority regarding which Convention Charts will be used for a given event.  Local clubs and units are able to decide which convention convention charts they feel to be appropriate for a given event.

For example, the club that I normally frequent has an "any thing" goes policy with respect to systems.  Its been a while since we had a pair playing a "strong pass" system, buts its been known to happen.

In Unit 25, most flight A events use the ACBL Midchart, though we do have occasional Superchart events.  Standard events use the General Convention Chart.

The ACBL defines the set of convention charts used in National events.  They tend to be MUCH more restrictive.

The very top events (the Vanderbilt, Spingold, and Reisinger use the Superchart).  

There are a very small number of Midchart events.  [Essentially only the top bracket of the Bracket KOs, which would be fine and dandy expect for the fact that they don't allow people to "play up"]

Everything else is GCC or LCC

[alanb]

The events that allow Mid-chart conventions are very limited.  The KO teams at a regional and the final few steps of National events.  I have two systems, a General chart and Mid-chart version, and almost never get to play the Mid-chart.

Forked bids like the Multi 2D can't be played at, say, a regional Swiss Teams or Flight A pairs.  Too scary for North America  .  I understand it is a pretty routine part of many systems in Europe, but here it impossible to play it even to get used to the darn thing, except in the KO events at Regionals.  

www.ACBL.org has the complete set of rules and restrictions.