Meg and I get a lot of our practice at Bridge Base Online. BBO is the world's premier bridge site... but we've talked about that before.
We were in the Partnership Bidding Room, working on our new big club structure. One of the very first hands was this one:
I was South, and opened 1C (16+ unbalanced or 17+ balanced). Pard bid 2C, showing a game forcing hand with long diamonds. 2D by me asked about her diamond suit. 2NT showed exactly five diamonds with two of the top three honors. 3C asked about aces and kings outside of diamonds. 3D showed no aces and at most one king. 3H by me was a cuebid, and when she cuebid 3S I knew it was a singleton (since she'd denied holding an aces). I cuebid 4C to get a little more information, and Meg came out with a brilliant bid -- 5C! She had a great hand for her previous actions, and wanted to do something slam-positive... so she cued her 'trick source' in clubs, and I bid the slam, knowing her hand to be x xxx(x?) AKxxx Q(J?)xx(x?).
No, it's not a huge deal to reach a good slam* with 11 HCP opposite 21, but I like to think we would have had the same auction if my SK were the S3. And if the SK was the SA, my bid would've been 7D over 5C!
* Slam should make on 3-2 diamonds, 3-3 hearts, the onside ace of spades, or West cashing the ace of spades at trick one -- I think it's over 80%.
How should this be played? Here's my suggestion: Say they lead a heart or a club. Win it in the closed hand [remember-- the big hand is playing it, I bid 2D], play a diamond to the ace and a spade down. If RHO takes the ace, all is well. If he doesn't, play the king -- if it holds, draw trumps and hope for 3-3 hearts for an overtrick. If the king of spades loses to the ace, win the return in hand, ruff a spade, draw a second round of trumps, and if all follow, play to ruff all three spade losers in the dummy before drawing the last trump. If diamonds are 4-1, draw trumps and hope hearts break.
Do you have a better line of play?