Photo Andrew Robson with the Queen
Source: http://andrewrobson.logonetwork.co.uk/ (Andrew Robson Bridge Club official site).
Small slams occur about one deal in 15: surprisingly common. Only if you’re worried about the number of Aces should you use Blackwood 4NT, or its modern version Roman Key Card Blackwood (RKCB). Think of Blackwood as a way of avoiding slam, not reaching slam.
Mostly you can bid a slam FAST, without Ace-asking…
F for Fit
Look for nine – even ten – trumps and you can make slam with many fewer than the 33 points for 6NT.
A for Aces
The partnership need all the aces or all but one. If you might be missing two, use Blackwood (or RKCB).
S for Shortages
Voids (especially) and singletons are hugely powerful when you have a big fit.
T for Two-loser suits
Be cautious when you have a suit with two (or more) quick losers. Even if you have all the other aces and kings, your slam will fail if the opponents can cash an ace-king.
You open 1 and partner bids 3 (Inv). With which of these hands should you go for slam?
(B). No. Poor shape (5332), and a two-loser club suit. Bid 4
(C). Yes. Excellent shape (5431), no two-loser suit, and a singleton. Bid 6.