“But as a strategy for teaching Git, it hasn’t been as successful as I’d hoped!”
The standard advice says learn Git’s internals and everything clicks. Git stores each commit as a full snapshot, packfiles compress those with deltas that are not diffs, and git show rebuilds two trees just to compute the diff you see. Evans polled Mastodon and found users split almost evenly between diffs and snapshots. When users cannot agree on what a commit is, the problem is the tool.