[Xiaolongnu]

I understand that transfer preempts, where 2NT, 3C, 3D and 3H implies the suit one step higher, either weak, strong or 2 suited, this convention is essentially green sticker. Does this mean that transfers in general are technically considered natural? The consequence of this that I am interested in is this. Suppose North opens 2NT, South did not notice and thought it was 1NT, and bids a "transfer" of 2D, making it insufficient. Is he allowed to make it 3D without penalty?

We assume, of course, that the Director has interviewed the offender in private and is sufficiently convinced that he really meant to bid a transfer. And personally I think that the UI involved in this infraction is minimal. Ok UI is not the correct word, what I meant is that the upset of equity is minimal.

[RMB1]

Xiaolongnu, on 2011-October-31, 11:09, said:

I understand that transfer preempts, where 2NT, 3C, 3D and 3H implies the suit one step higher, either weak, strong or 2 suited, this convention is essentially green sticker. Does this mean that transfers in general are technically considered natural? The consequence of this ...

Hi, and welcome.

I do not recognise the term "Green sticker" and I am not sure your first question has much to do with the second.

The WBF uses the term "Brown sticker" for opening bids (2C to 3S) that may be weak and do not show a suit. Transfer preempt openings (and overcalls) are not brown sticker if they promise 4 cards in the suit transfered to.

If an insufficient bid (2D) was intended as a transfer response (and the TD determines, away from the table, that this is the meaning of the insufficient bid) then it is possible that 3D will not silence offenders partner (under Law 27B1b). It does not matter whether the insufficient bid or the correction is natural.

[campboy]

I believe WBF system categories (green, blue, red, yellow) refer to the one-level openings. Higher openings may be "brown sticker", but this is not a separate system category; rather it is an addition to the basic category, so your system can be "green with brown sticker conventions" or similar. Transfer pre-empts are not natural but they are not brown sticker either.