How is "git reset HEAD~" "awkward"? It's not obviously named, but as was noted above, if there was git-uncommit, it would need every option that git-reset has, and so it would just be an alias, without the final argument.
"History is immutable" is generally accepted as describing the contents of commits, not their id's or relative ordering.
"History is immutable" is generally accepted as describing the contents of commits, not their id's or relative ordering.