Jinksy, on 2014-September-17, 15:49, said:
Curious: do others feel the same? My instinct matches jillybean's - with 4-card support for P, I'd very rarely bid a side suit first.
Some issues include:
1. Jacoby auctions, at least initially, are question and answer, and can't usually turn into cooperative dialogues until a high level and maybe not even then. There are many hands on which this works well, but in my experience they tend not to do very well when responder has a suit such as AJxxx or KQxxx or KJxxx. The problem isn't (usually) in game decisions but, rather, in slam and grand slam decisions, which usually entail more than just making sure we don't have quick losers. We'd like to know we don't have slow losers and/or we need to count winners.
Say we hold AJxxx and we bid 2/1 and partner raises. In a sophisticated partnership we will eventually be able to find out about the KQ of that suit as well as the AKQ of the major. Say he has Kxx in the suit. Well, given that we have 4 trump and this 5 card side suit, we probably don't have any pitch for his third card in the suit and we have a loser. Try identifying that on a Jacoby sequence.
Conversely, say we have Axxxx and partner doesn't raise. Now, if partner cues the King, we can (usually) place him with either stiff K or Kx, and in either case we have not only no loser but a chance, especially with Kx, of being able to establish an extra trick or two in the suit by ruffing. Again, try finding out his holding in most Jacoby structures.
2. In addition to inferences, or specific information, about holdings, letting partner know that we have length and strength in a side suit will cause him to appropriately upgrade good holdings and downgrade poor ones. When I am looking at Ax or Kx in a suit in which my partner makes a 2/1 and then shows me primary major support, I tend to get very optimistic in my hand valuation. When I hold xxx, I tend to get cautious.
3. While this is rare, there will be times when 3rd hand interferes. My own style these days is that when the opps start 1M 2N, as 3rd seat I strain to bid. I will come in on almost any decent suit....the other day I overcalled 3
♦ on KQJ109. Now, it was favourable, but my point is that very few players have any firm agreements as to how to handle interference. This means, especially if 2nd seat can raise the ante, or 3rd seat has a 4 level pre-empt, that it may be very, very useful for opener to have some idea of whether a double-fit exists.
These seem to me to be the main reasons why one should avoid the simplistic J2N weapon when holding a potential source of tricks in a 5 card or longer suit. Note that the arguments don't apply with similar force to side 4 card suits, especially since good jacoby methods allow for the finding of, and playing in when appropriate, of 4-4 side fits.
I am not saying that one should never use J2N with a side 5+ suit, but to my mind the suit had better be very good, such that we don't care about the difference, for example, between Kx and Kxx or xx and xxx.
'one of the great markers of the advance of human kindness is the howls you will hear from the Men of God' Johann Hari