Basal Bolus ratio should only ever be used when someone is diagnosed as a starting point from which to progress. Why? I hear you ask?
Well the two are doing different things. When you take a basal shot it is counteracting the glucose production that your body has in homeostasis and shouldn't be doing anything more. Your bolus should relate to food intake. On a day when you eat 300g carbs, you'd expect to have a very different bolus dose to a day where you ate 50g.
In the first case you may find that you are 30% basal, 70% bolus, and in the second, you would expect that your TDD will have reduced dramatically, but your basal will remain mostly the same, so the percentages may invert.
That's why the "ratio" model really isn't all that useful for most people, most of the time.