nige1, on 2016-October-08, 06:10, said:
1. Pass = NAT. Timid. Close decision. IMO you should open if opponents were vulnerable.
Interesting! I opened a hand that I would usually pass precisely because it was matchpoints, none vul - because I'd rather defend if I can get +100 instead of +90 but not +50 instead of +90. I tried to imagine why you would say you would open if the opponents were vulnerable (I am assuming you would open 1C.)
If it were IMPs, there would be more incentive to make it more difficult to bid their vulnerable game, but this is matchpoints so keeping them from bidding game has roughly the same value whether they are vul. or not. While competitive auctions are less accurate than constructive auctions, I can see that opening might make their hand evaluation better. For example:
If you don't open, the opponents have little chance of reaching 4S, in fact, unless your partner opens a 5-card weak two bid in third, the deal will likely be passed out.
However, when you open 1C, unless the opponents commit those awful minimum 4-4-2-3 or 4-3-3-3 doubles routinely, West knows he has a great hand on the auction. While I concede that this was constructed, there are many times where one of the opponents tries for game and the knowledge you have clubs will help them evaluate their hands better.
Another reason I thought of was a possible sacrifice, but unless you plan to bid again, partner won't know you have more than 3 clubs (or if you are playing that abomination "short club" or "5542", 2 clubs) so this isn't that likely.
If you think you'll get the best lead against their major suit contract, I'll grant you that, but again, in matchpoints, I don't think their vulnerability matters.
(Edit: had two DK's in the hand
)
I rank
1. Pass = NAT. Timid. Close decision. IMO you should open if opponents were vulnerable.
2. 1♣ = NAT, Longest and strongest (for lead). Over 1♥ reply, rebid 2♣. Over 1♠, 1N might be better.
3. 1♦ = Canapé. Some prefer this to 1♣.