One of the meta-agreements I have with my regular partners is that 2NT in competition is (almost) always artificial. There are some notable exceptions such as 1x - P - P - 2NT. But, most of the time it is either Lebensohl-like, two places to play, or scrambling. So partner is on the lookout whenenever a new situation arises. I don't know if its ideal, but it seems to work out fine.