The draft of Thornton in the third round I did not like at first not because of his talent, but because I thought better players could have been drafted with the pick.
Charley Casserly seems to like the pick though, labelling him a major steal:
"6) Hugh Thornton, OG, Illinois -- Indianapolis Colts, Round 3, No. 86 I like Thornton's strength and power as a blocker. He played left tackle last season at Illinois, but his best pro position is offensive guard. I love his quick set in pass protection. He has a strong punch and can anchor well as a pass blocker. In time, he could be the Colts' best offensive lineman." (http://www.nfl.com/news/story/0ap1000000165049/article/tank-carradine-marcus-lattimore-among-2013-nfl-draft-steals)
I really hope he's right