I would argue that unless you are reaching azeotrope then the ABV of the wash in your pot totally matters. Of course the still maters too, but both will affect the output ABV. Apologies for the inconsistency between numbers on the graph shown and the numbers I am talking about. When talking I was using a slightly different graph using fat fingers to "draw lines". The exact numbers do not matter, its just an illustration of the concept. If you are interested in using this graph I would very much suggest you spend some time reading these threads!