Boats should break Brittle Ice

When a boat slides over brittle ice blocks, it should affect them. Imagine a boat race with a brittle ice obstacle, if you pass over it multiple times, the ice should eventually break, changing the path. The same mechanic could apply to ice caves, when you're riding a boat over brittle ice, it should crack or break. If you stay on the same spot for too long, the ice should eventually break, causing you to fall through.