Specifically, they compared Chubon:
Show Image
(http://atri.misericordia.edu/Papers/Chubon/Chubon.jpg)
vs. Reverse QWERTY:
Show Image
(http://atri.misericordia.edu/Papers/Chubon/ReverseQWERTY.jpg)
This study was intended to test the following research hypotheses:
Hypothesis: The ReverseQWERTY keyboard will maintain the biomechanical relationships of the QWERTY keyboard while removing the effect of learning, allowing fair comparisons of alternative keyboard patterns.
So... you're comparing two layouts, in which one has an (upside down, wtf?) resemblance to the Qwerty letters, but puts the modfiers and Spacebar in very different locations; versus a layout that has the letters arranged differently, but has the spacebar and modifiers in their usual locations. What could you possibly conclude from such a study ?