Yes interesting a good word.

First could we stop talking about Rock Your World as a "turf horse?" Two starts
turf, one dirt. One stakes win on each surface. My biggest concern if I liked
him would be his relative lack of foundation. If I fancied him I would probably
want to see him have two longer works before Derby preferably at CD.

Maybe later I will search archives (free to all) to investigate history of
Derby runners who broke maiden on turf? Not expecting to find much. The truth
is that the only way we will see what might be considered a "turf horse"
running in the Derby is if a Euro turfer or North American runner with strictly
grass 2YO form runs 1-2 in a 100 point prep.

Barbaro and Sea Hero both had 2YO turf form but both (like Rock Your World)
also won major dirt races prior to winning their Derbies. Barbaro won the Holy
Bull and Florida Derby, Sea Hero won the Champagne and campaigned strictly on
dirt as a 3YO prepping for Derby.

Trivia uncovered: (a) Animal Kingdom is the only Kentucky Derby winner to win a
Grade I race at age 5? (b) Paul Mellon, owner of Sea Hero, only owner to win
Kentucky Derby, Epsom Derby (aka The Derby) and Prix Arc de Triomphe.