I agree with Robert’s reply and general questions. As a general model, I like the approach of going to a stadium for a ball game.
1. What stadium am I in? Wrigley Field or Candlestick. A screening DOE as a guide for factors and levels.
2. What Section are the seats located? The screening gives some insight but know you are judging where are we and where do we need to go? So, DOE #2 is a refining step.
3. What is my row and seat number? How exact must we be? Understanding main factors, or interested in possible interactions, or is a prediction model required.
4. We ok as is or do we want Club seating with AC and food delivery service? This would a very refined design with just a few critical factors.
Most DOE teams are very excited to see the results from step 2. This either confirms assumptions or dispels them or gives an insight not previously considered. Most techies want to go to step 3 for no other reason than curiosity.
Screen, sharpen, hone, sticking it!
A great tool that often yields surprises.
Ted