Cumulative Flow Chart in Kanban attracted my attention as I consider it a nice example of using branching efficiently.
IMHO, it is simply wrong to assume that every single task can be split into small fragments that are then iteratively incorporated into the mainline. The author calls this kind of task a “technically complex story”, and I have yet to see a successful example of migrating frameworks or doing technical migrations like that without resorting to branching. This is what the whole open source community does, and it is high time the “enterprise” world catches with these practices.
Branching then comes to the rescue ! Let the “technically complex story” evolve in its own branch, and make sure to conduct in-depth QA BEFORE the merge. Same thing for code reviews and going through the DONE checklist : make sure to do it BEFORE the merge so that you do not end up with non production-quality code in the mainline, which is then pretty hard to get rid of.