[hrothgar]

jeffford76, on 2013-February-18, 13:19, said:

I believe there is no way to get an official ACBL answer on whether a convention is legal under a particular chart.

This is true. However, to balance this out, its very easy to get multiple (conflicting) ACBL answers regarding whether conventions are legal, and many of these suggest that they are official...

[mycroft]

barmar, on 2013-February-15, 12:35, said:

That's because you're thinking of it wrong. They don't have general principles, and then systems that fit the principles are allowed. Instead, they decided which systems and conventions they wanted to allow (Precision, Jacoby 2NT, Drury are OK, Multi isn't) and then crafted the GCC in a way that it would allow what they wanted, without actually naming them (so the specific biases aren't overt).

Well, yes, but I believe it was the other way around.

Years ago, there were real convention charts, A to F, and they had conventions on them. And if you played them (the only way they were played, of course), you could, in events that included that chart or higher. (Now Justice) Amalya Kearse's Bridge Conventions Complete was exactly that, back then - if you could play it (in the ACBL), it was in Kearse's book, explained well enough to actually play it. Kind of fun, really.

But nobody played conventions exactly the same way, and they would keep on inventing new ones. So the ACBL moved to "you can play conventional X calls that say Y" charts, and made sure that the regular tournament games (that became GCC) could play all the stuff you could play at the old level (I believe it was Class C). So, of course, you can see that "we want to allow Romex Dynamic NT, and Precision 2♣ and 2♦, and Drury, and ..." in the GCC, to this day; you can also see that they want to be able to say "we don't like this kind of call".

Add 30 years of massaging (and after about 25 of them, they realized they had to update their "if you don't have a convention card, you're limited to Class A conventions..." spiel at every Nationals) you get the current GCC.

[Flem72]

CSGibson, on 2013-February-14, 21:29, said:

its not legal. Or, rather, if it were legal than it would also be legal to play Drury in all seats, and it is not. It would be legal if it promised game forcing values, but not as invitational+

IIRC, inv+ is GCC disallowed b/c Barry Crane played this way. And he won too much....

After thinking about this a while -- and it is one of the GCC rules that really pisses me me off, along with Kaplan Inversion -- it seems to me that 2C inv+ or C should be allowed so long as there are no Drury-like controls on weak openers. That, after all, was the problem with Crane's use of the structure: it was truly "all seat Drury." Why not allow it using a rule similar to psychic controls: OK so long as there is no rebid that announces the sub-min opener? Or is that too complicated for the masses? too much of a disadvantage to them?

This post has been edited by Flem72: 2013-February-20, 08:38

[blackshoe]

mycroft, on 2013-February-19, 17:02, said:

Add 30 years of massaging (and after about 25 of them, they realized they had to update their "if you don't have a convention card, you're limited to Class A conventions..." spiel at every Nationals) you get the current GCC.

That may well have happened because I (and perhaps other people, but I know I did) wrote in and pointed out that there's no such thing as "Class A conventions" these days.