Actually, if you want a prediction from common design, presumably it would be that we will find more function in those structures labeled as nonfunctional.
Pish-posh. Now you're dabbling in subjectivism. "Those vomeronasal organs are needed to retain the shape of the nose".
"That appendix has a function. It sits there, taking up space that would otherwise be empty".
"Whales need pelvises, because where else would their legs attach?"
Precision is something you often see in science, and rarely in Creationism. It's something I've harped on for a long time. A
hallmark of Creationism is a lack of
follow-through. A lack of precision. Airy ideas that never seem to get grounded in data, facts, or reality.
Take ye olde Vapour Canopy model. Any physicist who looked at the thing would immediatly wonder "If this is true, what would happen if...." and do a few back of the envelope calculations and note that "If the Vapor Canopy Model is true, then Noah would have been breathing superheated steam".
So much (virtually all, from what I've seen) of Creationism "science" (we're ignoring "why evolution is wrong" since false dichotomies are obviously pointless) is airy speculation with little to no attempts at falsification, or even an attempt to fit the thing into the real world. Hydrological sorting is an excellent example.
Anyone seriously trying to test such a theory would have immediatly run aground on certain problems. Big fat dinosaurs consistantly above tiny trilobites, for instance. But there was no serious attempt to test it. It wasn't a scientific theory, but an attempt to preach to the choir.