Basically this says, "git's UI was so bad that it forced me to learn the internals, and once I groked the internals git made a whole lot of sense." That summary might sound like I'm trolling but I don't think that's a bad thing (else, why is git so popular?). I've been the mercurial "expert" on my team at work for the past 5 years and I can't count the number of little DAG diagrams I've drawn trying to get people to understand what was really going on with their repository. I'm pretty sure there are a few people who still don't really understand how mercurial works under the hood. Maybe that's a positive aspect of mercurial...but maybe it's not :-)
Now, I will say that the internals of mercurial that you need to understand to gain enlightenment seem simpler to me than what you have to know for git. Mercurial has commits and commits have parent reference(s) that link commits together into a DAG. Commits might have a branch label. You move commits from one repo to another with push and pull. You create a commit with two parents by doing a merge. And that's it!
Git has those same basic concepts, but you also have to know about the index, and branches (which are really pointers to commits that may or may not be a branch in the DAG), and remote branches, and merges that aren't really merges because they just move the branch (which is a pointer, remember, that's why a "branch" can move) to the head, and all kinds of other interesting (and useful, no doubt) concepts.
Now, I will say that the internals of mercurial that you need to understand to gain enlightenment seem simpler to me than what you have to know for git. Mercurial has commits and commits have parent reference(s) that link commits together into a DAG. Commits might have a branch label. You move commits from one repo to another with push and pull. You create a commit with two parents by doing a merge. And that's it!
Git has those same basic concepts, but you also have to know about the index, and branches (which are really pointers to commits that may or may not be a branch in the DAG), and remote branches, and merges that aren't really merges because they just move the branch (which is a pointer, remember, that's why a "branch" can move) to the head, and all kinds of other interesting (and useful, no doubt) concepts.