The bottom line in this discussion is that DIII coaches are so very similar to DI coaches in that:
1. They know who they have returning at each position, including players who didn't get much playing time previously.
2. They know what new players are coming in (unless there are late surprises) and what positions they can potentially play, what their strengths and weaknesses are, etc.
3. They have a pretty good idea of what their depth chart looks like, which includes returning and new players.
4. And like DI coaches, they are ultimately going to play the players who will give their teams the best chance to win, no matter what class they are in, how experienced they are, how heavily they were recruited, etc.