How so? It sets a precedent for a president not to jail abortionists if that's the law, but would it really work the other way?
I guess the writer here is arguing that this decision is like the impoundment of appropriated funds, but after Watergate, Congress voted to severely restrict presidential power in that area.
Obama can cherry-pick the laws he wants to enforce. Ergo, we can choose to ignore the precedent set by Roe v Wade. With that ruling out of the way, we would revert to previous more restrictive abortion laws. It should work both ways.