Respectfully, I have to disagree.
Let's say that a RB with top-10 grade miraculously falls to 51. Now, no doubt, we're loaded at RB, but in the big-picture, Choice was a 4th round pick with a much lower draft grade in his class. So theoretically, you've improved an already stacked position.
I understand that evaluations get screwed up all the time, and Choice has proven that he can play in the NFL, no doubt, but if you can add theoretically better talent to the position, you do so.
Then, you can flip Choice for a pick which was better than his actual draft position. Who knows? Perhaps you could get a second round pick in the next years draft.
BPA!