Marcel Christ creates a series of photographs in which he work on commercials. In most of his work, he used plain background to show the dominance of the subject for the viewer. He also used one light comparing to Gregg Schapps. He likes to do his work playful and with movement on the subject.
Gregg Schapps creates photographs where he used colorful background, sometimes with patterns. Comparing to Marcel Christ, he used couple lights, which are background light and also a light which comes in a perspective way in 45 degree angle. Usage of light he likely experiments shadows on the subject. In my opinion, Gregg Schapps becomes more successful on making a high contrast on his photographs than Marcel Christ.
I am not sure how you get to the idea that Christ uses one light and Schapps two lights. I assume each uses differing numbers of lights depending on the shot. You do make a good point that Christ uses motion-wow to those splashes-while Schappscreates simple bold flat shapes.