Same preamble as for new minor forcing really "After originally learning basic Acol with very few bells and whistles, I sometimes find aspects of GiB 2/1 rather complex, unnecessarily so, and occasionally so highly constrained that some sequences can get me into trouble - and if I didn't have the tooltips would not have a clue what some bids/systems actually mean
I'm not getting into really obscure ones but this one is one of the more commonly used forcing bids that occasionally causes me problems because we are looking at NT but it gives me no indication of Spade holding at all
Eventually you just take the plunge and hope there isnt a gaping hole in your contract somewhere"
- taking the plunge in NT without having a clue about partners spades in this case
Note. Ran a quick Sim based on information at the point of fourth suit force
Mean NT by south is approx 8.5 with standard deviation of 1.5 and range of 2 to 13
1NT and 2NT bids are fairly safe so maybe its not too bad