Obviously I have already determined what the max black is with just the procedure you describe or I would not have been able to know what time to use. But thanks anyway. I do use test strips for split grade printing, but that's about all.
I thinks it's better to learn what key your neg is singing in and then go from there. It's like music, you will never be able to play anything with any passion if you don't know what the different notes sound like in your head.