When you first learn about the bidding, everything is structured around how may points you have. The high card points system is the first guideline you learn but that is exactly what it is – a guideline. As you play more and more, you realise that your distribution or ‘shape’ plays a big role in how many tricks you make, and it isn’t necessarily just down to how many points you have.
Expanding on this idea further, it would be wrong not to evaluate hands based on their shape as well as their high cards – this is where the ‘rule of 20’ comes in. The rule of 20 is a different way of evaluating as to whether your hand should be considered an opening hand or not and it is as follows:
If the sum of your points plus the number of cards in your two longest suits is equal to or greater than 20, then your hand should be considered an opening hand
For example, if you consider these two hands, which one would you say is better?
This one:
♠ Kxxx
♥ QJ
♦ QJx
♣ Kxxx
Or:
♠ AK10xx
♥ x
♦ xx
♣ K10xxx
You could argue that either hand could be better depending on the situation, but if spades or clubs end up as trumps then certainly the second hand is better. This is down to the fact that the second hand has much better shape and should be considered as at least equal to the first hand.
When you consider weak 2 hands, the rule of 20 has implications there because when you have a 6 card suit, your next longest suit must be at least 3 cards in length so you only need 11 points to meet the rule of 20 and therefore open the bidding at the 1 level (11+6+3=20). This means that a weak 2 is limited to 10 points because if you meet the rule of 20 then you should be opening at the 1 level.
Consider this hand:
♠ AKJxxx
♥ Qxx
♦ xxx
♣ x
Using the formula for the rule of 20, you do not meet the requirements to open at the 1 level (10+6+3) but you can still open a weak 2 as normal.
Change your hand to:
♠ AKJxxx
♥ QJx
♦ xxx
♣ x
And now you meet the rule of 20 and should therefore be opening at the 1 level. A key thing to remember here is that there is no ‘gap’ with a pre-emptive style hand. Either you are opening it a weak 2 (or 3 or higher!) or you are opening it as a normal opening hand at the 1 level.
Below are a few examples of hands that would not normally qualify as an opening hand but now do because they meet the rule of 20:
♠ Axxx
♥ Jx
♦ KQJxx
♣ xx
♠ KJx
♥ AKxxxx
♦ xx
♣ xx
♠ KQJxxxx
♥ x
♦ Axx
♣ xx
♠ x
♥ xx
♦ KJxxx
♣ AQxxx
