[barmar]

Trinidad, on 2015-June-30, 23:15, said:

Some people I know play it as a maximum with a five card major.

If I want to show that, I jump to 3 of the major.

[helene_t]

One advantage of playing it as a minimum with 4-4 majors is that it allows you to play nonpromisory while at the same time having
1NT-2♣
2♥-2♠*
show an invitational hand with 5+ spades. It loses when responder has a weak hand with moth majors but in that case we often have a double fit, maybe even a 9-card fit, and the fact that opps didn't do anything (for example doubling 2♣) makes this less likely than a priori anyway.

It also loses when we find a heart fit and at the same time tell opps whether opener has spades or not.