It looks basically just like a Git repository. Mining is like competing for a chance to merge a bunch of other people's commits (because you get a "commit fee"

It looks basically just like a Git repository. Mining is like competing for a chance to merge a bunch of other people's commits (because you get a "commit fee" for each of them). And you always want to merge into the longest repository, because otherwise you're receiving those commit fees in a fork that's unlikely to be cared about.