[smerriman]

After a strong 1NT opening bid and 2NT response, all bridge teaching material will tell you the same thing - accept with a maximum 17 points, pass with a minimum 15 points, and use your judgement with 16 points.

Yet nobody seems to go beyond that and actually explain what you're meant to be judging. With a completely balanced hand, there doesn't seem to be too much to judge on. Accept always because you don't want to miss out on game and trust your own card play skills? Start counting 9s and 10s? Add extra points for aces which are undervalued and Qs and Js which are overvalued? Is it better for the points to be spread out, or concentrated?

[PhantomSac]

Holdings like HH doubleton are bad (QJ doubleton especially)
Holdings like HHH tripleton are bad
Five card suits especially with texture are good (KJT9x is a lot better than KJ432)
Tens and 9s are good especially when combined with 4 card suits (AJT9 is clearly better than AJ32)

[PhantomSac]

Aces are really not undervalued at NT unless combined with a trick source (then they are very valuable). For instance I'd pass an invite with A432 A43 A32 A32 in a heart beat. They are undervalued for suit contracts and when a trick source is available more than anything else. Of course if you hit your partner with KQxxx and a K that would be a good game!

[WesleyC]

There has been a fair amount of discussion on this topic and most players now lean towards the idea that you should 'invite conservatively but accept aggressively'. The idea here, is that you would much rather play 1NT or 3NT than 2NT.

Using this style, the norm is to invite with 9 HCP (or possibly 8 HCP and a 5c suit) and then accept the invite with anything other than your most minimum 1NT openers.

[1eyedjack]

WesleyC, on 2015-October-14, 22:36, said:

There has been a fair amount of discussion on this topic and most players now lean towards the idea that you should 'invite conservatively but accept aggressively'. The idea here, is that you would much rather play 1NT or 3NT than 2NT.

Using this style, the norm is to invite with 9 HCP (or possibly 8 HCP and a 5c suit) and then accept the invite with anything other than your most minimum 1NT openers.

Scoring makes a difference here. Going one more down in 3N at IMP is no disaster (unless doubled). Going one fewer down in 2N than a room in 3N is a result at MP. Getting doubled is a disaster at IMP, perhaps slightly less so at MP, and is a concern although in reality tends to be low frequency.