Rafal - not sure why you are against using different grades of paper, split filtering etc. These are tools, not crutches. You mentioned John Sexton - who knows a thing or two about making good negatives. Yet, it is not uncommon for a single print to require all of the following:
-Extensive burning/dodging and/or multiple grades
Making good negatives is important, but I disagree with the notion the goal of testing should be to use a single paper grade. Particularly when high contrast lighting is involved, targeting specific paper grades can cost you.