to test Hutch's new pic attachment

I attach this pic.
My question: This is a nowaday Basic pattern from Rundschau. In the past the pattern were done in another way. The back was smaller (see the 1 cm at the back dart, it takes away 1 cm from the armhole width), the Armhole was parted 1/2 and 1/2 not like in today's one 1/3 to 2/3. And front was made shorter 1 cm and back 1 cm longer. And the bust dart was calculated in quite another way (here not shown).
I started patternmaking in the early 80 ties. There were those alterations already done. But I have books from the 50 ties. There was the older draft. Now I'm looking for the time when the change began and can get maybe some explanations.
In my opinion it could be 2 reasons:
a)With the new draft you could easier do all kind of sleeves, like set in, dolman, kimono, raglan from the same basic.
b) The posture was not so erect anymore.
Maybe some has older literature?
lg
posaune
it works wonderful, Hutch! Thanks to both of you Lepus and Hutch.