1. What would 3N mean, by either player: an offer to play 3N

Clearly inappropriate by either player
2. What to bid over the 3
♠? Your choices appear to include: pass, double (responsive) 4
♣, 4
♦ or 4N, minors
Pass is out. We are vulnerable, at imps. I have long believed that it is appropriate, when advancing a takeout double to assume partner to be 4441, with a stiff in the opps' suit: and (unless you hold an Ace or two) to be x Axxx Axxx Axxx.
A takeout double of a 2
♠ bid should deliver, at its low end, a tad more than a takeout double of 1
♠, so assuming, here, x Axxx Axxx Axxx is not unreasonable.
Opposite that hand, passing is a terrible call: no way can/should partner reopen with that hand, yet we have missed a good vulnerable game in order to defend a contract they might even make.
Double, as responsive, would be fine if partner is assured to pull to a minor: he will not pull to a 4 card
♥ suit, so we will be fine UNLESS he passes. He might well pass with a chunky 2=4=3=4 or so, and lead a trump. While we might still go plus, it will be touch and go, especially if the
♥ suit sits well for them: imagine dummy with Axx J109xx Kxx xx and declarer with KQxxxx Kxx xx xx: partner with Jx Axxx AQx AJxx.
4 minor is a middle ground, but, once again, partner cannot know when to raise: with the x Axxx Axxx Axxx hand, he really ought to be passing 4 minor, and yet we'd love to be in game, even tho it is not cold.
4N assures us of getting to our 9 card fit, which is potentially important. It assures us of getting to game.... unfortunately, it does not assure us of making that game!
There is a warning sign (misleading on the actual hand) in that North, at favourable, bid only 3
♠ with, probably 4 trump. Of course, at this heat, he has to cater to his partner havng only 5 spades and he may have terrible shape: with a big LTC, even a 10 card fit may not suffice.
Furthermore, 3
♠ offers East the chance to be conservative: I'd expect a lot more votes for 4N over 4
♠ than over 3
♠: a point sometimes lost on the busy preemptors.
I was impressed by jdonn's post but, as is apparent, I don't agree with his choices. I am bidding 4N, not because I have seen the west hand but because, not having seen it, as East I'd be scared of missing game more than I'm scared of -200... or even 500.
West might have xx AKJx KQx Jxxx and I will be sorry. He might have x Axxx Axxx Axxx and I will be happy.
Should West raise 4N beyond 5
♣?
I wouldn't: east is under pressure and west, altho he has an excellent hand, should be happy with game: in these situations, a partnership should have a clear understanding that under pressure, the game bidder should be given a lot of latitude. West should allow East to have overbid at this vulnerability.. if the
♦Q comes down, I missed a indifferent slam... big deal, at least I got to my game.
If east chose to bid a suit over 3
♠, I'd go with 4
♦ in case of the (unlikely) chance to bid again.... and as west, now I would bid 5: the purity of the hand, and the need to bid games, drives me to it.
While West should cut East a lot of slack when East bids 4N, forcing to game, the same is not true when East bids 4minor: this is NOT forcing, and invites playing a partscore... east tends to be full values for this type of call, and, in that context, West has (just) enough extra to warrant game.
You can see from this analysis that bidding either 4 minor or 4N by east reaches game while avoiding (a possibly making) slam. Thus it is not surprising that I consider it very close between 4minor and 4N.
The reasons I choose the more aggressive 4N is that:
1. 4N assures us of reaching the correct suit.. the suit in which, if we are too high, we are least likely to get hammered in (and may play a trick better: picture west with xx AKJx Axx Axxx: we pitch 3
♦ on the
♥, and avoid losing 2 tricks to north's KQxx... heck, if they lead S's stiff
♦, I make 5
♣!
2. We are red at imps
3. 4 minor puts way too much load on partner to bid game when its right.. far more load than I want him to have.
'one of the great markers of the advance of human kindness is the howls you will hear from the Men of God' Johann Hari