This is one of my biggest pain points with hg vs git: Git is actually the one that flat-out prevents me from rebasing most of the time, usually for the most spurious of reasons, whereas hg just lets me choose to auto-rebase most files and pick the ones I'm interested in to manually merge.

And makes a mess of conflicts. I would rather not be able to do those things than to fix a conflict of a head with the working files on HG.