bluenikki, on 2020-July-23, 10:36, said:
This is your *last* chance to show ♦ support, rather than tolerance.
It's problematic to raise with mins even if you exclude trash like this example hand. There's just not enough room to show extras below 3nt.
It is not the last chance to show diamond support; later support can be real support because tolerance hands can mostly rebid M or NT or a 4th suit scramble (1s-2d-2s-3c-3h!). It's not like partial auctions where you are frequently needing to show tolerance for a 2 level partial without a real fit.
Showing support isn't that useful with the weaker hands when a very large percentage of the time 3nt is the target vs 5m.