The line was run blocking well throughout the second half of 2013. Garrett refused to run the ball in the second half of 2013. Sturm has stated both of those things.
Yes, down the stretch in 2013 the line was improved, and Garrett did not run the ball heavily. Sturm has said that, and I have said as well that failing to notice the run blocking was working at times like in the Green Bay game was a really bad coaching error.
It can't be more black and white than that. If Garrett was calling the plays now, he'd call it the same way he called plays in 2013. The improvement in the line didn't affect him in 2013, it wouldn't affect him now.
No, this conclusion does not logically follow. You act as if a couple games of increase performance would have been enough to convince him to throw out what he had planned on doing all season.
It is logical to say "he should have realized and adjusted better" but it is NOT logical to say "this is proof he didn't want to run." Coaches are going to re-evaluate where they are and what they are doing in the offseason. After watching the tape of 2013, it would have made sense that they'd say, as a staff, "Whoa... Look at this line down the stretch. Now that we have Martin and growth from Frederick and Leary, we're gonna be even better this year. Let's work this into our game plans for the coming season."
This especially seems the more likely case when you figure
1) Garrett clearly is not philosophically opposed to running as evidenced by his allowing it to happen within the frame of his offense this year as well as his commitment to running it in 2007-08 in his offense as well, and
2) The fact that Linehan was not someone who you can honestly sell as a run-heavy playcaller, so for me to believe that it's "all him" instead of a collaboration and product of circumstances (the line personnel) would be absurd.