When is a bid Theta?
Theta is used in only two situations:
- A simple new suit bid over the response to a low-level Beta (not in Responder's suit).
eg: 1♣-1NT(Bal Positive)-2♣(Beta)-2♠(4 Controls)-3♦
is Theta in Diamonds.
- A Repeat Alpha in the same suit is Theta...
...(unless Responder has shown a balanced hand in which case it is Iota).
(Note: A Repeat Alpha in a different suit is always Iota and never Theta).
If Responder shows a balanced positive with 1♠, then a bid which would otherwise be Theta is not Theta but Iota, the collapsed version of Theta, because with a balanced hand the worst holding Responder can have is xx.
