1
James' system does a pretty good job or reflecting "conventional wisdom" of how feared an opponent's starting pitcher is by home team fans, but it is seriously deficient in its response time. It fails to crown the supernovas who immediately are the most unhittable pitchers in the game until they "prove it" for 2+ years. Paxton is obviously an Ace+ and Felix is only maybe/kinda/sorta still a 3.
But for the others, I think it does a decent job of capturing the pecking order as it stands.
For another take, the FiveThirtyEight pitcher ratings list Erasmo as our current #1 starter:
Erasmo Ramirez 49.0 +9
Ariel Miranda 47.6 +3
Andrew Albers 44.4 -12
Marco Gonzales 43.2 -18
Yovani Gallardo 42.8 -20