[Zelandakh]

There was a book written in the Master series (thus 'official') which spent alot of time on sequences with 2 suits being supported and 4th suit forcing, in fact these 2 sets of sequences were almost the whole book! It is a long time ago (early 90s I think) but as I recall the recommended approach was that if the second suit is a minor it is definitely (game) forcing. If the second suit is a major then the author was more circumspect, saying there were advantages to either approach. But in the end he suggested that the positives from making it forcing outweighed the positives from having this available as an invite. That said, it is non-forcing without a special agreement otherwise but, in my experience, almost never passed in practise.

[nige1]

Lurpoa, on 2011-April-23, 04:17, said:

please, can you verify Crowhurst..... if non forcing, what were his reasons ?
Stong or weak NT: the inviting goes trough 1♥ 3♥: no need to mention ♣

On p212 of Precision Bidding in Acol (1974), Eric Crowhurst recommends that 1♥ - 2♦ -; 3♦ - 3♥ be invitational but non-forcing
- 1♥ = Could be four cards
- 2♦ = Usually 9+ HCP. At least four cards. Forcing for one round.
- 3♦ = Limit raise. Minimum opening bid with at least four card support. Implies five hearts. Not forcing.
- 3♥ = Three cards. Invitational but not forcing.
Opener can pass, correct to 4♦, raise to 4♥, bid 3♠ (as a notrump probe), or even bid 3N (all natural).

[Lurpoa]

nige1, on 2011-April-25, 21:36, said:

On p212 of Precision Bidding in Acol (1974), Eric Crowhurst recommends that 1♥ - 2♦ -; 3♦ - 3♥ be invitational but non-forcing
- 1♥ = Could be four cards
- 2♦ = Usually 9+ HCP. At least four cards. Forcing for one round.
- 3♦ = Limit raise. Minimum opening bid with at least four card support. Implies five hearts. Not forcing.
- 3♥ = Three cards. Invitational but not forcing.
Opener can pass, correct to 4♦, raise to 4♥, bid 3♠ (as a notrump probe), or even bid 3N (all natural).

As said, yes, I fully agree. I was wrong (too focused on 5card major systems).
Mea Culpa.

[whereagles]

I don't quite agree with

1M 2m
3m

being non-forcing. Say responder has 10-12. How is he going to find out whether opener has 11 or 14? You might be missing out on cold games and bid to unmakable ones.

It's much better to bid

1M 2m
2M

with a min and 5 cards, rather than 3m. Responder always has the strength to bid 2NT anyway, after which you can show delayed support for the minor and weak hand. Note that in acol opener can't have 4 cards (would open a weak NT or rebid 2NT with 15-17).

[gnasher]

whereagles, on 2011-April-26, 06:03, said:

I don't quite agree with

1M 2m
3m

being non-forcing. Say responder has 10-12. How is he going to find out whether opener has 11 or 14? You might be missing out on cold games and bid to unmakable ones.

It's much better to bid

1M 2m
2M

with a min and 5 cards, rather than 3m. Responder always has the strength to bid 2NT anyway, after which you can show delayed support for the minor and weak hand. Note that in acol opener can't have 4 cards (would open a weak NT or rebid 2NT with 15-17).

Isn't that just another way of saying that you just don't agree with playing Acol?

[helene_t]

Whereagles, I didn't start this thread to ask what peoples' favourite system is. My question is which of these sequences are forcing in English Acol.

Now that question may be a little misty since English Acol has for some time not been played by many experts, so depending of whether the question is "how do expert partneships playing Acol play it", "how do most better club players play it" or "how is it taught to beginners" you may get three different answers.

But 1M-2m-3m is very clearly non-forcing in either case. The thing is, 1M-2m-2M is nonforcing - it is not true that responder has the strength to 2NT, he may have 9 HCPs and opener may have 11. So if one would have to rebid 2M with a minimum and minor suit support, there is a real possibility of playing 2M in a 5-1 fit while a 5-5 fit in the minor is available. The 2M rebid is overloaded enough as it already is.

[whereagles]

@gnasher: no, it's another way to say that acol's old adage "all raises in acol are limit-bids" isn't the most efficient way to bid. Acol is a fine system as it is. Just not optimal. But hey all generalist systems are far from being the most efficient in their category.

@helene: where did I say I prefer this or that system? Anyway, the problem you mention (playing the 5-1 fit with an 8 card one available) is mitigable with some minor tweaks. The problem I rose rates to be more troublesome.

[NickRW]

helene_t, on 2011-April-22, 03:30, said:

Playing English Acol, uncontested:
1♥-2♣
3♣-3♥

The average club player can and will pass 3♥ with a min in my both current and past experience.

Whether this is a good idea or not is another question entirely - but then you start asking whether Acol is a good idea.

Nick