I hope I'm putting this in the correct forum.
Under Stock Convention Cards, the BBO Advanced 1.3 card includes this explanation for the 3N bid:
"Signoff. running clubs; d/h stops; short spades". I presume that is supposed to be running diamonds, with c/h stops.
Also, the descriptions of 1x-1y-3N are not quite consistent. They are:
1♣-1♦-3N: Non-forcing, ♣ source of Tricks.
1♣-1♥-3N: Signoff. running c; short h.
1♣-1♠-3N: Signoff. running c; d/h stops; short spades.
1♦-1♥-3N: Signoff. running d; short in h.
1♦-1♠-3N: Signoff. running clubs[sic]; d[sic]/h stops; short spades.
If bidding 3N over 1S shows stops in the two unbid suits, doesn't bidding 3N over 1H or 1D also show that? Is the suit-quality standard different for 1C-1D-3N than for 1m-1M-3N, or does "source of Tricks" = "running"?
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1D-1S-3N in BBO Advanced 1.3
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