You've got to try and make it scientific, though I agree with T-Graph about the viability of a racing surface. Still the danger is giving a horse a number because he ran it before. I still disagree with the numbers Commendable earned. I thought his win was a freakish day and surface result. Second by seven lengths to Tiznow, he still earned another two. Which I could have sworn was a three then. The bottom line is you'll never get horses to behave as nicely as the projections in hypotheticals and you shouldn't try.