Even though I posted an answer that uses the same module I upvoted this node because it was nice to see that same module used in a slightly different way. (Plus I was pleased to see that someone besides me is aware of the module's existence.)

In a future version of the module I intend for validation failures to stash additional information that error can retrieve from its parameter list so that error doesn't need to try to figure out all over again why validate failed. ...so something of a try/catch notion.