Natural 5 card major

System Summery

General approach and style
Natural, with weak NT
(semi) constructive but aggressive bidding
Could be weak in sandwich and third hand

Special bids that may require defense
2: Multi
2/: (9)10-13 HCP 6/7 card
3NT: Solid Major 10-15 HCP
4/: 4/ opening with unknown minor (6/5 like hand)

Leads and Signals

Opening and subsequent leads
1 (singleton , doubleton, highest of a series with a honer) / 3 / 5

Signaling
Low is on or even.
Generally attitude before count in partners suit (except after King lead), and count in opponents suit.

Lavinthal principles

Psychics

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Third hand: common bridge, openings could be (very) light
After weak NT pass -> transfers to a major could be with 0/2 HCP with 2+ card

Doubles

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In general doubles are takeout, except after partner has a defined range in
length and strength, like after a weak (or a 2M) opening

Doubles out of the blue at game level or above are also penalty and have tendency to ask for a specific / special lead

Defensive and Competitive Bidding

Overcalls in direct position
Constructive overcalls, near opening quality en some weaker with a 6 card
Could be little lighter after partner has passed


Overcalls in sandwitch
Could be light specially after a open pass
Dbl; 5 card highest remaining suit / 4 card lowest remaining suit
1 NT; 4 card highest remaining suit / 5 card lowest remaining suit
2 NT; 5-5
Rest is real even their suits


Jump overcalls
2 / 9-13 6/7 card (responses see 2M opening)
All other jumps are weak and 6+ card


Cue and 2NT overcalls
Cue: both highest suits, weak or strong, max 5 looser hand
2 NT: both lowest suits, weak or strong, max 5 looser hand
Responses: bid a know suit at any level is to play
Lowest remaining suit SI in lowest suit
Highest remaining suit SI in highest suit


After weak and mini NT (DOWN)
Pass: any 11-17
if they pass- > pass (let them have it); dbl (some points); 2x 6+ card to weak to defend.
If they bid �¨ double shows points, any else a good 5+ card


Dbl; any 0-5 / any 6-8 5+ card / any 18+
if they pass �¨ pass and see what happens; 2x 6+ card
if they XX �¨ pass and see what happens; 2x 6+ card (if xx shows points)


2: any 5-8 HCP any 4333 / 4+ 4+ higher suit
2: any 5-8 HCP 4+/ 4+ /
2: any 5-8 HCP 4+/ 4+
2 - 3: two suiters with max 5 losers (/////)


After strong NT
Landy / 2NT as random 2 suiter


After they double out weak NT (Twisted Swine)
Pass: forces to XX, either to play or run with /
XX: forces to 2 -> (pass correct) with singlesuiter
2: and a major; 2:; 2:; 3x preempt