[mytailorisrich]

No, I mean small chunks that are actually merged instead of having a stack of them floating around.

A rebase before a merge can always happen, of course. But there are not stacked commits then it is just a standard rebase of your small chunk and that's it. And this will also have a shorter life than a stack so rebases will be rarer and simpler.

[happytoexplain]

Oh, yes - but this is more about your situation than your style. Sometimes a feature is large and varied enough to beg multiple PRs, yet singular enough that you are not developing them serially (i.e. as you work on later parts, you are changing earlier parts). Most of the time this isn't the case.

[mytailorisrich]

My experience is that you should always aim for frequent small commits. This is what continuous integration and trunk-based development advocate and it saves a lot of headaches and the need to come up with "exotic" solutions to problems created by big, long-lived dev branches.

This is quite orthogonal to developing parts serially or not, and it is perfectly fine to change or refactor ealier parts when you work on later parts. Development is an iterative process.

It seems to me that "stacked diffs" are an example of looking for a technical solution to process issue.