A few months or a year ago a Google designer quit when he was forced to split test one too many shades of blue. He described what a creativity sink the uniform fidelity to that sort of approach is. Of course, in a large organization there are always counter examples and counterpoints, but that particular Google designer was responding to frustrations inspired by recognition of this post's observations. Engineering has not yet reached the point where split testing is always (or usually, in my opinion), better and more efficient than the creativity of a trained expert.