Fourth Suit Forcing

[Lovera]

About 4th Suit Forcing(=FSF) priorities and useing conditions i've found these two YouTube videos :

1)

2)

(Lovera)

[helene_t]

Marlowe has given one reason for having an agreement where FSF is always game forcing (except for the example you give) even if bid at the 2 level. I'd like to know if there are other reasons.

The main reason for playing 4sfg is that whenever either partner has a queen more than he had already promised, he can just make his normal bid without worrying if partner passes him in a partscore. Pairs who play 4sf not gf will sometimes have to jump to avoid that but you'd prefer jumps to be very specific, not just a queen extra

[Lovera]

Also can be interesting to have conditions about force and answers priorities when FSF is applied by opener.

[pescetom]

but (as far as I am aware, please correct me if i'm wrong) there is only one scenario where the 4th suit is not forcing to game: the auction 1♣ - 1♦ - 1♥ - 1♠, and on this occasion the 1♠ bid is an actual suit.

 

I can think of some other scenarios depending on the conventions one plays.

 

Playing short club openings, there is no FSF possible when the auction opens 1♣ and there is ANY response at 1-level, because 2♣ is always available as a "new" suit: so not only is your example above true, but 1♣ - 1♦ - 1♥ - 2♣ is equally forcing one time and denies an actual suit of spades.

 

Playing 2/1 as unconditionally game forcing, I wouldn't call the fourth suit (as in question 3 above) FSF, as the game force was already in place and implications like fast arrivals may be different and remain in place.

 

Plus of course playing XYZ or similar a 2♣ or 2♦ fourth suit may have a meaning defined by the convention.

[Lovera]

I've found another site about FSF and when is used also by opener: http://www.pattayabridge.com/conventions/4thsuitforcing_main.htm