If you use a bleach within reason and regenerate it by oxidation (even a Jobo can do this with rotary action induced aeration in a blank (no film) run), it will about double the Kodak or Fuji figures if not triple it. The key is overuse and image degradation.

You can possibly test the bleach by adding some AgNO3 in Acetic Acid. If you get a good cloudy precipitate in fresh bleach, then compare this to a well used one. The well used one will not form as much precipitate. Or try a small piece of copper such as an old copper penny. A bleach should dissolve one. So measure with used bleach. (I have not run these tests with the newest bleach, but have with RA4 blix).