In what part of installing stage is "make.conf" co

[volar]

As for my understanding,
the system must take consider of the configuration during anytime
"emerge" is used, right?
How about when bootstrapping(scripts/bootstrap.sh)?

I'm currently installing gentoo from so-called "stage1",
so I think my question is:
When a USE-flag is changed, how far I have to roll back
to redo some of the procedures again?
Or is it something only like "emerge system" necessary?

Thanks for helping!

[gentoo_lan]

Changing the USE flags in an emerge system should be good enough.