Why 1S instead of 1H?

[chuck and teril swart]

In responses to minor suit openings section B-1 it states that with 8 points or less

to bid "normally 1H with both majors, but prefer 1S with 4-4 in the majors if 6 or a bad 7 points"

This is not present in older KS books and it risks losing a 4-4 heart fit (although it does make the auction

1m 1H 1S ? more awkward.) Why is this change in KSU?

[Michelangelo Di Stefano Medico Psicoterapeuta]

See B-6 and B-7 and you'll understand.

1m-1♥-1♠ may be unbalanced, exceptionally 3-card and responder's 2♠ is invitational 9-11, while 3♠ is game forcing, strong.