Partner opens the auction with a Weak Two bid and then your RHO intervenes

Question

Can the Ogust convention still be used?

Answer 1

You have my permission to use it, if RHO doubles or bids 2♠! Whether it's a good idea to have that agreement is up to you and your partner.

Answer 2

The McCabe convention, briefly, gives you the following options after opponent doubles after your partner opens a weak two:

• A new suit as cheaply as possible: A lead-directing raise of partner's suit. If LHO passes, your partner will rebid their suit. If LHO bids, your partner should lead the suit you've bid.
• 2NT: Whatever 2NT would have been without interference.
• Redouble: A single-suited hand, usually with a void in partner's suit but essentially always with 7 cards or better in our own suit -- essentially, a reason to believe that your suit provides a better place to play than partner's. If your LHO passes, partner will bid the cheapest suit so that you can pass or correct.

If opponents intervene in another way, one reasonable way to play is that bids mean the same thing they would without interference (so 2NT would still be Ogust if that's your agreement). Note that double by responder after opener's preempt is always for penalties.

Answer 3

As (almost) always here, all the other answers are correct. However, a question arises (hinted at with AdamW's answer) about efficiency. In other words, "You can. Should you?"

Now, of course, if the opponents' intervention is at the 3+ level, you can't bid 2NT. Ignoring that...

What is the point of Ogust (or any other 2NT inquiry)? It is to find out if partner's opener has the right cards for game (in their suit or in NT, usually. If you're looking for "right cards for game in my suit", almost always the "right cards" are in that suit, and so bidding it (forcing) to find out is the way to do that).

Now, a common bridge aphorism is "you don't preempt over a preempt". There are good reasons for that, but it's outside the scope of this question. The relevance here is "when they intervene, they have stuff". Now, if your game doesn't ascribe to that bit of bridge wisdom, then maybe the case for Ogust is more prominent (and the case for "don't care what the field does, we don't preempt over a preempt" raises even higher. You'll get the good results from partner knowing you have stuff, and the good results from the opponents not counting on you for it).

But in a normal field:

When you intervene over a 1-level opening bid, is your system designed around finding game? or competing for partscore? The latter, obviously (yes, there are games when the opponents open at the 1 level. Yes, they're good to get to. But 90% of these auctions are either "compete for partscore" or "work out if we should sacrifice over their game"/"find the right lead against their contract").

It's the same here. LHO has "opened" over your partner's "overcall" (with playing strength, in their suit at least). How often are you looking for game, as opposed to competing for partscore, or raising the preempt, or determining if the sacrifice is there?

Another question is: assuming RHO lets partner answer, how much do you want the opponents to know the answer to "how good is your weak 2/where are your cards"? If your side the one with game, then you're telling the opponents if they should sacrifice or defend; if they're the ones with values, how much is that worth to the "two-way guesses"/"finesse or drop" analysis?

I have switched to the style ruds sets out (although I know it with a different set of convention names). We actually have 2NT as an explicit "does not have a meaning" I guess we could play it as Ogust, still, but our preempt style, being more aggressive than normal, makes it even less likely we have game on power, and more likely that "just bid game, either it makes or it's better than their 140, without telling the opponents what's in opener's hand" is the right decision.

If you play sound/"disciplined" weak 2s, you may consider switching 2NT and XX - yes, it means you're forced to the 3 level of your "my suit is better than yours", even if it is higher than partner's, but fitting with "double by preempter's partner is always for penalties", you get the "partner, they have stepped out here" immediate flag that pass (which could also, and usually does, mean "oh good, I'm glad they're going to let us off the hook") does not. And if opener has the 6=4 that partner can't cover (or KQx, or), when they run to that suit, they get to double.