I finally finished my first playthrough, Leon A on Hardcore, but I am now realizing that what they probably intend is for you to do Leon/Claire A on Normal and then Leon/Claire B on Hardcore. The downside of that approach is that you miss out on the combination of everything being both new and challenging at the same time, so I'm still pretty happy I made the choice I did. I finished with a lot of healing items, save ribbons, and ammo, so I was clearly too conservative. That also led to why it took so long. I didn't turn it on unless I had multiple hours free so that I could thoroughly explore and minimize saves.