We had an auction the other day (last board of a late online session) where I accidentally opened a balanced 16 count in 2nd seat 1NT. My partner responded 2H (on a pleasant 11 count) which was a signoff, and there should be no way whatsoever that I could pull this. I was still in strong NT mode though, so I bid 2S. Partner passed this and we made 9 tricks in our 4-2 fit. Whoops. Partner was as confused as I was when dummy came down.
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My 2S bid should tell partner that I actually have 14-16, as I shouldn't be able to pull 2H if I had a 10-12 hand (psyches withstanding).
A few questions/scenarios:
1) My partner figures from my 2S bid that I messed up. Is he allowed to take another bid or try to place the contract (at his own risk, of course)?
2a) Suppose I realize I messed up after my 2S bid and my partner takes another bid. Am I obligated to behave in any particular way?
2b) Suppose I realize I messed up after partner's 2H bid (intended as a signoff). Am I allowed to take another action at my own risk, even though our agreement on this auction at this vulnerability is that 2H is a signoff?
Of course, if I'm just playing at a table and my partner announces my range as 10-12, I'm screwed either way, but lets suppose partner doesn't announce or there's screens or whatnot (in the case that happened, we were on BBO so partner didn't alert, of course)
Thanks!