user:vang:vang_-_donsabin

- vang - donsabin system notes

vang - donsabin system notes

natural, 5 card majors, better minor, 15-17 NT, 2/1 style

carding

standard honor leads, 4th at notrump, 3/5 at suit.
ace lead usually ask italian signal; king lead usually ask count
lead direct count in partner bid suit
attitude - low encourages; normal count; first discard italian;

slam bidding

KCBW 14 30 2 2+Q

weak 2

2D/H/S weak, may be 5 cards. 2NT ogust
- after ogust, 3C shows a 5 card suit and then 3D ask → 3H=minimum, 3S=maximum

strong 2C

2C the only strong opening. 22+HCP if balanced.
- kokish relay: 2C - 2D - 2NT=22-24 BAL; 2C - 2D - 2H = GF BAL or hearts; 2S ask (mnemo here: longer path is stronger).
- when we can stop below game:
  - 2C - 2D - 2S - 3C (second negative) - 3S
  - 2C - 2D - 2NT (22-24 BAL)
  - 2C - 2D - 2H - 2S - 3H (hearts, NF)

checkback after NT rebids

double checkback after 1NT rebid
special 3C checkback after 2NT rebid:
- 1m - 1M - 2NT - 3C*
  - ... 3D=both 3 card support and other major in 4
  - ... 3NT=none of those
- 1m - 1M - 2NT - 3D* = to play in M or SI with 4cM and 5c other minor
- 1m - 1M - 2NT - 4m = natural SI (4cMaj and fit 5 in minor)
- 1m - 1M - 2NT - 4om = autosplinter

fit in majors

fit in majors
- 2NT = GF fit 4. then, level 3 = natural, level 4=splinters; 3NT=15-17 BAL; 4M=minimal, no splinter, no side suit
- jump1 = INV fit 3
- jump2 = INV fit 4
- jump3 (just under bid M) = mixed raise fit 4
- after jump1/2/3 - relay=ask for shortages. Major rebid=no shortage; suits=singleton; NT=short in upper suit

2/1 sequences

2/1 is GF except when a opener does NOT show extra-values and reponder rebid his minor
1S - 2H - 2S - 3H = GF
1M - 2/1 - 2M = stall bid; anything above this level shows extra-values from opener (and creates GF)

after our overcalls

rubens advances - after our non-jump overcall on any level, transfers starting with cuebid (uncluded) to fit. NT is always natural. rubens advances does NOT apply after balancing overcalls or when 3rd hand bids direct fit or higher.

fit in minors

1m - jump other minor = mixed raise (~ 7-9 HCP)
inverted minor raise. 2NT shows minimum balanced and can be passed. 3m shows minimum UNBAL and can be passed

18-19 balanced with 4 card fit

1C - 1M - 3D = 18-19 BAL fit4
1D - 1S - 3H = 18-19 BAL fit4 or SPL. 3NT ask, 4S=BAL
1D - 1H - 3S = 18-19 BAL fit4 or SPL. 3NT ask, 4H=BAL

misc

support doubles and redoubles
lebensohl after 1NT - overcall.
lebensohl and good-bad in many other positions / ??? /
reverse drury fit
after our 1NT doubled - ???
18-20 one-suiter ???
multi-landy over adverse 1NT
our 1NT - 3x = ???
NO puppet stayman
transfers after 1M - (X), starting with 1NT (→ clubs)
1m - 2M = weak