[AlexJonson]

---

All non-vulnerable,teams of four, for better or worse South deals and opens 3♦.

West passes, North gives it significant thought and bids 3♠.

Regular partnership, but nothing on the card.

Legal bids?

[mfa1010]

Any bid is legal. Partner could be thinking about a lot of things. If south passes and he is right, it would look a little ugly though, passing a presumably forcing bid after a tank.

[peachy]

If it can be determined what the BIT likely means, then there would be actions indicated by the BIT and some of those LAs would be ruled illegal. I don't see how it could be determined what the UI from this BIT is (other than the responder was probably unsure of what to bid) so opener is free to act as he pleases. However, if 3S is forcing, he should not be passing.

[FrancesHinden]

Wot peachy said.

[AlexJonson]

Thanks for the commments.

I clearly went too far in assuming North was considering 3NT, and therefore had something in diamonds, making 4♦ a safe bid.

My presumptions did coincidentally correspond to reality. Luckily enough, from an ethical perspective, 3♠ passed out was a poor contract and a poor result.

[mycroft]

I would wonder if partner is sub-standard for a force, myself. But I'm bidding 4D - I don't have support.
Easier if I'm playing A-Z responses to preempts; I bid 4D, first-round spade control (but, of course, I'm not).

Over Here, 3D-p-3S is forcing absent agreement - so no info means pass is suspicious. Other juridictions/communities mileage may vary.