Summary: Derek Sherrod might need to get a pep talk similar to what Sandra Bullock (playing Leigh Anne Tuohy) gave Michael Oher in The Blind Side. He has the size and athletic ability to play left tackle in the NFL, but could be too timid to deal with some of the more aggressive pass rushers. Almost everything else checks out, and in a generally weak draft class, he is one of the top tackles expected to be able to man the left side.
I realize it is hard to know intimate details about every team in the league. But Ballard didn't need to address Luck's protection. Over the last half of the season the Colts offensive line showed major improvement. They have a solid player in Haeg and Clark went from completely worthless in preseason action to being a serviceable RT by the last 4 games. I expect the growth from Kelly across the right side of the line to be enough to have fixed the OL. Grigson was mostly worthless outside of 2012 draft but his parting gift of the 2016 draft class of lineman might have finally been the OL answer.
I understand you think from your perspective, but by now you should understand you do not come close to thinking like the Seahawks F.O., as a fan I have come to embrace not knowing their thought pattern and enjoy the ride. Many would feel you are along the lines of what the old-school GM of the Colts said of Mel Kiper. But your site keeps me amused at times