Not the Question wrote:
Those aren't competitor's versions of the 4%...
Berg is referring to the Hoka Carbon X, Skechers GoRun Razor Elite, the Saucony Prototype Ward wore at Boston, and the new Adidas Prototype that has been floating around.
To answer the original question, those models weren't tested by the study.
They just proved what all the other tests have shown it works. Combination of the plate and midsole foam create a more reactive shoe.
My guess is that they are trying to get a baseline for the Saucony product to compete with the 4% to say its better.
Different labs will give different results due to equipment variables and testing parameters.
What needs to happen is to gather all the flex plate shoes in one lab with all with consistent variables and see what shoe performs best.
Added to this study needs to be the variable of elite efficient athletes vs average runner and its benefit to athlete differences.