This is certainly....something? Cam Inman spoke with Jimmie Ward and Jaquiski Tartt on Tuesday, and they had some intriguing insight into general manager Trent Baalke. According to both players, Baalke is down at the practice field frequently, and will correct technique and offer other coaching at times. Give the article a read here, which includes some quotations from Ward and Tartt.
I don't even really know what to make of this entirely. I asked a couple media friends who have covered other teams in recent years, and they did not think this was normal.
Baalke spent much of the early part of his career as a scout. He spent three seasons with the New York Jets as a scout, from 1998 to 2000. He then moved on to Washington, where he served three years as a national scout, and one year as college scouting coordinator. Finally, he joined the San Francisco 49ers. He was western region scout from 2005 to 2007, director of player personnel in 2008 and 2009, VP of player personnel in 2010, and then general manager starting in 2011.
All that is to say, I'm not entirely sure why the GM is coaching up players. He does seem like a grinder type who loves that kind of stuff, but it seems a little odd.