Relation between steel brake line and performance?

Question

I was suggested to change the brake line to steel and it would improve braking performance. I am curious as to how this would improve braking. Does the stock line expand and steel braided one does not? How does the steel brake line help the braking performance?

Answer 1

That sounds plausible.

Answer 2

Honestly it is more cosmetic than anything else, there will be a minor improvement in pedal feel but there are a lot of more substantial things that can be replaced to improve braking performance. (aftermarket calipers, slotted discs, etc.)