Is "Liking the Surface" At Churchill Overrated?

[Late Fires]

One of the reasons that I like Street Sense, Circular Quay and Any Given Saturday so much in the Derby is that all are proven over the Churchill strip. But as I look back at past Derby winners, it seems that you have to go back to Lil E Tee to find a Derby winner that had won a race prior to the Derby at Churchill. Am I putting too much stock into the fact that a horse is proven to "like the surface" at Churchill?