You may have a point. But it may also be a distinction without a difference. I'm not going to argue your semantics (or mine). But does the expression , "God was able to use that error in judgment for profit..." fail to take in, or consider the wisdom that comes from experience? (See Romans 5)
1Therefore, since we have been justified through faith, we have peace with God through our Lord Jesus Christ, 2through whom we have gained access by faith into this grace in which we now stand. And we boast in the hope of the glory of God. 3Not only so, but we also glory in our sufferings, because we know that suffering produces perseverance; 4perseverance, character; and character, hope. 5And hope does not put us to shame, because God’s love has been poured out into our hearts through the Holy Spirit, who has been given to us.
And might "gained access by faith into this grace wherein we now stand," presuppose that we have to abstain from making errors in judgment in order to benefit from that access into grace?
Nevertheless, what you posed suggests an intriguing quandary and/or paradox.