JanM, on Feb 2 2009, 07:33 PM, said:
As far as the legality of 1♦ showing spades: ...
[*]That bid is clearly not GCC legal; it isn't a catchall 1♦ bid and that's the only way it would qualify under the GCC.
...
I posted this list in another thread recently. I am sure I could expand on it.
Jan, which are clearly GCC legal and which not? And the more important question - how do you tell?
1. Acol or Goren etc
1♣/1♦ Natural 4+
2. Standard
1♣ Natural 3+ only three with a balanced hand without four diamonds
1♦ Natural 3+ only three with precisely 4=4=3=2 distribution
3. Preferred Minor on suit quality
1♣ Natural 3+ only three with a balanced hand without four diamonds
1♦ Natural 3+ only three with a balanced hand can be 3=3 in the minors
4. Short Club
1♣ Natural or Balanced 2+
1♦ Natural
5. Precision
1♣ 16+ (or 13+ or whatever) unlimited distribution
1♦ Natural (can be canape with clubs)
6. Precision with short diamond
1♣ 16+ any
1♦ Natural or Balanced 2+
7. Precision with 1+ diamond
1♣ 16+ any
1♦ Natural or Balanced or any 4-4-4-1
8. Precision with 0+ diamond
1♣ 16+ any
1♦ Natural or Balanced or any 4-4-4-1 or 4=4=0=5 with bad clubs
9. Symmetric Diamond (without the relays of course)
1♣ 16+ any
1♦ Two or three suit unbalanced no five-card major (in other words length in either minor)
10. Matchpoint Precision
1♣ 16+
1♦ Promises an undisclosed 4-card major
5-10 could be repeated (perhaps with some changes) for strong diamond systems.
11. Omnibus Club
1♣ Natural or Balanced or any 4-4-4-1
1♦ 5+
12. MidMac
1♣ Guarantees one or both 4-card major(s)
1♦ Denies a 4-card major
13. Diamond Major
1♣ Denies a 4-card major
1♦ Promises one or both 4-card major(s)
14. Transfer Openings
1♣ 4+ hearts
1♦ 4+ spades
15. Tied Major
1♣ balanced or long minor with exactly 4 hearts
1♦ balanced or long minor with exactly 4 spades
16. Canape
1♣ Natural (3+) Canape - could have a 5+ major
1♦ Natural (3+) Canape - could have a 5+ major
17.
1♣ Natural or Balanced
1♦ Natural or Balanced
with Balaned open 1♣/♦ at random
18.
1♣ Natural or Balanced 12-14
1♦ Natural or Balanced 18-19
other ranges would be possible
19. Polish Club variations
1♣ Natural or Balanced or Artificial Strong
1♦ Natural
There are variations on this where 1♦ is less natural.