There may be a small problem. Since Scott will know he's part of an experiment, his behavior/technique may change. I think the best way to eliminate this bias would be for someone to sneak into Scott's house, switch two of his razors and two strops, leave them for a certain amount of time, then sneak back in, switch the items back, and finally have an outside party test those razors. A blindfold might help too, but that could get a little dangerous.
On a serious note, whoever tests the razors at the end should have other razors thrown into the mix and not know which are from Scott.