While the stacked code review process at Google is pretty smooth - if you're using the default version control system, keeping your chain in sync is a nightmare

While the stacked code review process at Google is pretty smooth - if you're using the default version control system, keeping your chain in sync is a nightmare. If C depends on B depends on A and you made a modification in A, there's no automatic way to rebase anything and you have to start patching B then C manually. It's much much easier with the internal version of Mercurial, but the default VCS doesn't support this method.