Tom Warren is done for the season and Glyn Hughes has a torn hamstring so will miss most of the playoffs. Ryan Glynn has been a bench player for Saints during the 6 Nations and had some limited game time.
I would have thought that once Saints are full-strength following the end of the 6 Nations we'll see Glynn, Morgensen and Ingle more regularly. With internationals away and many senior players given the week off this week, the Premiership clubs use this time to blood as many academy players as possible - hence LV Cup weekends coinciding with international weekends.