Mandell Bids

Chapter 05

Interference over 1NT or 1NT overcall

Systems on: over artificial X and 2♣ (not for majors). Also essentially on vs 2NT overcall.
Lebensohl off if you pass and they balance
Over 2♣ or 2♦ for Majors: See below, don’t need Stayman. Uses S and NT to invitational transfer to C and D. Direct bids are weaker.
Over 2♦ – single major: still xfer leb, pass then X 2M is takeout, X and X is penalty
Over 2-Level Not for Majors: Use Transfer Lebensohl or Negative Double
Over 2NT and above: See transfer systems below
Transfers. Essentially where room using transfers. 2♦♥♠. 3♣♦. 3♠. 4♣. (3♦ is flip)
Not Transfers. 2NT (stayman and Jacoby). 3♥ (need a bid to leave room for 3NT [3♠] and one to show spades [X]).
DONT runout: over penalty X
Texas On in competition through 1NT-4♣. Not transfers into their known suits. Not after 1NT-4♦.
Radu over 2♦, 2♥, 2♠: semi stoppers and stoppers, giving up on 6+C GF. 1NT-3♦-3♠ GF.

Negative Doubles/Takeout: replaces Stayman: 1) perfect takeout 4-7, 2) Can handle the auction (4-7), 3) Invitational 8+. 2NT by Opener is scrambling over (2M).
1NT-(2X)-2NT-3♣:
Weak hands: Sign-off bids
~~Cue for Clubs:~~ ~~6+ clubs GF (Radu plays this as semi stopper, same as he plays after his weak 2 Leb and Leb after 1m-(2M))~~ semi-stopper
6♣+4M, Bid Above 3X: If could have made 2-level bid of M, 2N-3♣-3M is 6+C and 4M (1NT-(2♦)-2NT-3♣-3♥).
~~3NT, Slow Shows.~~ ~~2NT then 3NT shows stopper. 3NT direct denies.~~
Direct Cue: Asking for stopper, shortness
Transfers at 3-level: Skip their suit, show 5+ invitational or better
Opener: accepting shows min unless fit makes you want to upgrade. Can cue with max, no fit, not stopper. Can super accept and show stopper above 3NT (1NT-(2♥)-3♦ (spades inv+)-4♣)
3M 55m GF: If they showed S, 3♥ bid not used so 55m GF. If they showed H, 3♠ bid not used so 55m GF
Re-entering: X of natural is takeout, X of artificial is natural

X Values: invitational strength 8+ (forcing to 2NT or penalty), then X penalty (4#), P waiting (after waiting can X or show stoppers or 5+ minor)
2♦: After 2♣ for majors 2♦ is 5+ and less than invitational
2♥ for minors: Competitive with both minors
2♠/2N Transfers: Inv+ for C/D
3m to play
3M: 55+ splinter *(can be 54 4/21/25 hand with Radu 9 Jxx K8xx KJ98x)*

2NT for minors: X good hand (game going), 3♣ Stayman, 3♦ 5+ H Inv+, 3♥ 5+ S Inv+
3♣: X negative, 3♦/H/S 5+ for H/S/D Inv+/Inv+/GF
3♦: X negative, Flip, 3♥ 5+S Inv+, 3♠ 5+ H GF
3♥: X = 4 or 5 spades, 3♠ = GF with 0-3 spades, 4m natural, 4♥ Texas.
3♠: X = negative (usually 4♥), 4♣ = D, 4♦ = H, 4♥ = C, all GF
4♣: X = Negative, 4♦ = H, 4♥= S, 4♠=D
4♦: X = negative, 4♥ = Natural, 4♠ = Natural

X of 1NT: Systems on if artificial, DON’T runout if penalty (also if they bid 2♣ not for the majors, our double is Stayman and systems on)
X of Jacoby: If they lead-directing double transfer: Accept transfer with 3-card support, pass with 2-card support, XX would be business but unlikely
X of Stayman (P denies): Re-Stayman if lead directing and you P (no stopper), then XX is re-stayman if needed. Note for Radu: Not playing switch on XX
If they overcall after our 2♣: X is Penalty, bid oM if you have it, pass with neither of those