TylerE, on 2013-February-15, 09:23, said:
This was a system I was introduced to by a partner of mine - I am unsure if it's a creation of his, or something he learned from someone else, but I quite like it and have had good results playing it.
Bids are as follows.
1♠-1NT: Semi-forcing, never 3♠
1♠-2♠: Normal 3 card raise
1♠-2NT: Jacoby
1♠-3♣: 4 card raise, 6-12
1♠-3♣-3♦: Range ask
1♠-3♣-3♦-3♠: Minimum
1♠-3♣-3♦-Anything else: good 9-12, anything besides 4♠ shows a source of tricks. 3N suggests playing it there.
1♠-3♦: 3 card limit
1♠-3♠: Preemptive
The main problem with this structure is that 3
♣ covers such a wide range. Yes, opener can make an artificial game try in your structure to distinguish between 6-bad9 and good9-12, but that is all. If 1
♠-3
♣ shows a traditional limit raise, then Opener can still use 3
♦ as an artificial game try, but now to distinguish (say) 9-10 from 11-12.
Worse still, if 4th hand makes an overcall above 3M, Opener will have to guess as he does not have the luxury of a game try available as the partnership has not shown enough strength to play pass as forcing.
TylerE, on 2013-February-15, 09:23, said:
There are a number of advantages of this system over standard Bergen raises....
- It allows you play 1N as only semi-forcing (Or I suppose, even non-forcing), if you wish.
Why's that an advantage? It's perfectly possible to include hands with 3-card support within the semi-forcing 1NT response. If Opener passes 1NT, that contract is often safer than 3M.
It's also perfectly playable for 3-card limit raises to start with a 2-level bid.
Quote
With a 4 card non-preemptive raise it hides responder's strength unless opener actually needs to know
Not for long, as there is normally a clue fom the sight of dummy! Of more consequence is that your 3
♣ bid will make Opener reveal information about his hand strength (from the fact that he bid 3
♦, or from he fact that he
didn't bid 3
♦).
Quote
Always an immediate fit-showing bid with 3+ support
Disambiguates the auction 1M-1N(*)-2x-2M (Now shows exactly 2 card support)
This is not necessarily an advantage either. If the opponents are considering whether to protect, it's much harder for them when they don't know whether you have a fit or not.