Scorekeeper

https://github.com/gschorkopf/frolfr/issues/43
The only thing I'm concerned about is that if a user has unsaved data and they hit the previous round button (or navigate away at all by any means other than hitting the next round button), the data won't get saved, and there won't be any indication that the data hasn't been saved. They're just going to find out later, when they reload the page and realize that their scores weren't saved. 
I know you're concerned about making a bunch of unnecessary requests, but I'm still thinking this is worth more consideration from a UX perspective.