DOM operations (node insertions, deletions) are trivial. It's the CSS reflow/relayout that's expensive. Though that can be trivially solved by preparing a shado

DOM operations (node insertions, deletions) are trivial. It's the CSS reflow/relayout that's expensive. Though that can be trivially solved by preparing a shadow DOM off-screen, then finally replacing the changed fragment by the newly build-up one. DOM diffing is just a convenient method to do it.