Interesting. Just read from DK that when the Steelers initially brought in Turner, it had nothing to do with DD. They brought Turner in because Big Dot wasn't taking his conditioning seriously enough and they were thinking of having Turner come in to take DOTSON'S spot.
"I'm told, by an impeccable source, that the initial motivation for summoning Turner was a general dissatisfaction among the coaching staff with the offseason regimen of young
Kevin Dotson and that, as a result, there was a very real worry that he'd be a viable candidate to start at left guard. ... But Dotson, apparently, could -- and did -- wait to take his offseason seriously, in the eyes of management. I wasn't told any specifics, other than that it had to do with conditioning. And that management, with all the other uncertainty on the offensive line, was in no mood to wait for Dotson to get set straight."
Link provided, but it's a pay site and this is an insider article for subscribers:
https://www.dkpittsburghsports.com/...of-shape-steelers-nfl-column-grind-opinion-dk
Big Dot it seems was taking his spot for granted and not putting in the work to be his best. The Steelers bringing in Turner the first time was a shot across the bow to wake Dotson up and let him know that nothing is a lock for him.