I'm not even sure if that's what it's called.
On some canoes like this Nymph (https://www.clcboats.com/images/2022/catalog2022/leadphotos/nymph-canoe_lead.jpg), the tumblehome has a hard angle (is that still a chine?) and then the top top four inches or so are concave. What's the advantage of that shape? Is it just for some more clearance for your hand?