[mycroft]

So, three times in this past week (once with the robots), I have had 6-7ish high after 1x-1NT, with at least an 8-card fit. Not enough to double, but what should I think about (if anything) viz. raising vs passing? I've always been a strong believer in "show your fits", but with the points and the trumps stacked against us...

The three results were 2♠+1, 2♥-1 (still a decent score, but I guess -100 would have been less so), and 2♦-4. The last one (oddly enough, that was the +140) twigged me to think about this in general.

[jallerton]

In general, you don't want to let the opponents play in 1NT when you know you have a fit your way. I think you need to be a bit more cautious about rasing when you hold only low cards in the trump suit as the trump finesses do not rate to work.

[gnasher]

The 1NT overcall may mean that the cards are badly placed for our side, but it also makes the hand easier to play if we're declaring, because we'll know where the high cards are. The overcaller may give a trick on the lead, or he may be endplayable later.

In 1NT, on the other hand, it will be hard to get the defence right, because partner won't know where your high cards are.

Before you heard the 1NT overcall, you were expecting to make about eight tricks in your trump suit. Even if that expectation has reduced to seven (an overestimate), it will still usually be right to bid.

[gwnn]

I think you underestimated your overestimation, gnasher. When you raise 1M to 2M, usually you don't go down, so your expectation is well above 8 tricks. The expectation does go down but it still stays close to or above 8, I would think. So it is definitely right to bid 2M.

[helene_t]

I think it's right to show partner your fit before it is too late. He may be able to compete to the three-level if LHO bids over your raise.