I don’t think there’s any reason you’d expect that to beat DIPS in a way that doesn’t show up in the data via low ev on ground balls or something. The exit velo on the ground balls he gives up is actually above average IIRC. There’s really nothing to suggest we should expect Sanchez to keep beating his DIPS and 550 innings or whatever isn’t a huge sample. The best explanation at this point is that he got lucky.
Sanchez hasn’t ever induced weak contact. We were all fooled by a small sample into thinking he was a FIP beater. He’s just a gas can who has no business starting MLB games.
I think it was you guys I acquired him for in BORED in exchange for Brett Phillips like 4 years ago, and I rostered him until I rage-dropped him this year (which I regret because I'm now using Ivan Nova). He's a very serviceable back end starter.