bluejak, on 2012-May-08, 09:57, said:
1♥ was described as "asking for heart stop for NT, 6-7". It was intended as natural, 6-7. N/S had system notes: they showed 1♦ dbl 1 ♥ as natural, but without reference to the meaning of double. North poiinted out that in analogous situations where an opponent shows two known suits, bidding one of them asks for a stop.
Based purely on the evidence in this thread, I would tend to rule MI, although I would investigate what they mean by 'analogous' situations. Here are some examples (based on my systemic agreements):
-if an opponent shows a suit at a low level (e.g. opening 2D to show both majors, overcalling 1NT with 2C for the majors, making a Michaels cue-bid) then we play a bid of one of their suits as natural if they have only promised 4 cards and artificial if they have promised 5+ cards.
- after a negative double we play a 1-level suit bid as natural (1C 1H dbl 1S), but after a transfer response we play a 'cue' as artificial
- if an opponent makes any form of 2- or 3-suited take-out double, we play bids as natural
The third point is relevant. After a nebulous 1C opening, double described as, say, 'take-out but with emphasis on the majors', how would they play a bid of 1M? (or a transfer, if that's what they play)?
The point I'm trying to make, is that if I'd had this problem I could come up with 'analogous' sequences where a bid of their suit is artificial, but some different 'analogous' sequences where it's natural. After all, if the pair in the OP had the agreement that _all_ bids of opponents' suits were always artificial, they wouldn't have had the problem that led to the ruling....