There is actually an automatic mining in broodwar ... But how does it work?

If you send 3 or 2 workers to a mineral patch, they sometimes split automatic…

Iam not sure how it works exactly, but i have noticed that it depends on who near the other patches are, nearer better …
The way the workers go to the patch and mine …
If there is a curve they wont got to the patch against this curve …
and pressumable the worker count … though 2 seems to work more times 3 is also possible … MAybe even more …
Sombody knows something about this ? …
Since, it is good to split … But often it seems you would have been better off with a bad split because they split automaticly …
some inside?