This happened to me in my draft, but with Maurice Morris instead of Turner. He drafted MM in the end of 15th(out of 16) while I drafted Norwood, his guys backup, in the 14th round (before Duckett's trade).
So I had Dunn's backup, and he drafted M&M as ransom to get Norwood on his team, knowing I'd want to insure my #1 pick Alexander.
First, he tried trading straight up. Then Duckett got traded, and Norwood did well in the preseason. EVEN then I was reluctant to trade with him because of his kidnapping strategy, but I have a deep RB roster (Shaun Alexander, Ronnie Brown, MBIII, Cedric Benson, Deangelo Williams) and solid at other positions, so I felt I could gamble a bit and sell Norwood to him and benefit next year from it.
For my 14th round pick this year of Norwood, I got Maurice Morris and his 7th round pick next year. I feel like I wouldn't have done much with Norwood this year, and getting a fairly good draft pick next year at this point in the season was good value.
I realllly wanted to hang onto Norwood, but being without my star players backup just left my season uncertain. I have a title shot this year, and I need to insure my top player, and in the process, I picked up a 7th round pick next year.
So that is what I gave up to get my studs handcuff, although I realize the situation wasn't much like yours.
I like Bob's post in that 75% of the time you come out good. I agree and if you can take the gamble for a few games, he'll likely drop him in favor of a sleeper WR or a bye week fill-in.