I use the "stackless" stacked PR git workflow mentioned in the article. I also add a bit of niceness to it so I don't have to remember the commit IDs:

So git has a notes feature, this is a simple note attached to a commit. It's intended for adding extra context to commit messages without changing the commit hash. Then there is a gitconfig for having these notes _follow_ the commit through rewrites such as rebases, squashes, amends, etc,.

All this together means that you write the branch name that you want in the note, use the git notes commands to two-way map this to the commit. Wrap this all in a git alias and it's golden.