Quote
. . .
b) natural no trump opening bids and overcalls, except that direct calls,
other than the following, must have at least one known suit.
- Double
- Two Clubs
- Two Diamonds showing a one suited hand in hearts or spades
So (1NT) and then:
x = transfer to ♣ but if then ♦ = red suits, or ♥ = ♥ + ♣ or ♠ = ♠ + ♣ (weakish)
2♣ = transfer to ♦ but if then ♥ = MAJs or ♠ = ♠ + ♦ (weakish)
2♦ = one suited ♥s or ♠s
2♥ = ♥ + minor (INV)
2♠ = ♠ + minor (INV)
2NT = minors
Over strong ♣ bids (1 or 2):
x = transfer to ♦ but if then ♥ = MAJs or ♠ = ♠ + minor (weakish)
♦ = transfer to ♥ but if then ♠ = ♠ + minor (stronger)
♥ = transfer to ♠ but if then NT or ♣ = minors (strong/weak)
♠ = transfer to ♣ but if then ♦ = red suits
NT = relay to better minor with 6-5 or better distribution in any two suits