Sometimes the cable/brake hook up allows one to get a lot of cable slack (as in center pulls or canties or with segmented rear cable casing) but other times loosening the cable at the caliper anchor bolt makes things so much easier to deal with. Sometimes that loosening comes with "discoveries" about cable or caliper condition
Having a rear cable/casing on hand can get the job dome quickly, in case the cable is wanting replacement. I often transfer the old rear cable to the front then too.
BTW I found when I was in high school that my dominate hand was better at modulating the front brake so that's how I've set up all my bikes since. Andy