Previously, we debunked the Rule of 7. What about the Rule of 17?

 
First of all, who can memorize all these rules? If you must know, the Rule of 17 is used when partner opens a weak two-bid. It's purpose is to tell you if you should look for game. It goes like this:

THE RULE OF 17: When partner opens 2 or 2, add your HCP to your number of trumps (partner's suit). If the total is less than 17, there is no game. If the total is 17 or more, you can explore game. (If it is really high, you might just bid game or slam).


For example:

 K2  
 Q54  
 AQJ87  
 K32.
 

Partner opens 2. You have 15 HCP + 2 spades = 17. You should look for game.*


Another example:

 5  
 KQ98  
 AQ98  
 KJ42.
 

Partner opens 2. You have 15 HCP + 1 spade = 16. You should pass 2.

Do I like this rule? Not really. It is a crude guideline which might have appeal to new players. But, as usual, I prefer thinking and judgment. What is partner's preempting style? Was he vulnerable?  Was he in second seat?  Consider this hand:

 KQ2  
 AQJ875  
 --  
 6543.

Partner opens 2. You have 12 HCP + 3 spades = 15. The "Rule of 17" says no game.

Nonsense. If partner opened a vulnerable 2 (especially in 2nd position), I would just bid 4. It would be laydown opposite as little as:

 AJ10865  
 K2  
 862  
 72.
 
--and that is surely a minimum for 2nd seat unfavorable. It would have great play opposite as little as:

 AJ10873  
 104  
 632  
 82
 
(a hand I wouldn't even open vulnerable).

On the other hand (pardon the pun), here is a "17" (16+1 = 17) where I wouldn't look for game:

 5  
 KQ72  
 KJ87  
 AQJ4. If partner dealt at favorable vulnerability and opened 2, I would pass and hope for the best. (I'd really like to make a takeout double, but they don't allow that). My partner's white on red 2 is likely to look like:

 KJ8762  
 85  
 62  
 K82.
 
If you put the two hands together, you'll be hoping you can make 2 (and don't even think about notrump).

Aces/kings/tricks are much more important than HCP. Having AK, A, A in the side suits is much more useful than having queen-jacks which are likely useless. 

Also, the Rule of 17 fails to take ruffing values into consideration. If you have Kxx in trump support and a singleton on the side, that is obviously much better than Kxx in trump support and 3-3-4 in the other suits.

Holding QJx in partner's trump suit is surely more valuable than if it were in a side suit (the Rule of 17 would count either as simply 3 HCP).

I haven't even mentioned IMPS versus Matchpoints. When Vulnerable at IMPs, you try harder to bid games. Form of scoring, position, vulnerability and partner's style all are factors.

 
Summary: The Rule of 17 (like most rules) is a guideline--no more. I don't recommend that experienced players use it. It is more of a learning crutch for newer players.

*The way to look for game is to respond 2NT. This asks partner not only for a Feature, but if he is minimum or maximum. He should show a feature only with a maximum. If he is minimum, he should repeat his suit (and you will usually give up on game). If he is "medium" he must decide which way to go.

 

Updated: Aug 2020