The good news for Jonathan Williams is that LeSean McCoy is ahead of him on the depth chart. Why? Shady is not a goal-line back, and with Mike Gillislee gone, Williams will get the coveted scoring opportunities. Williams will get more than the 27 carries he had his rookie year and will most likely carry the ball 10 times per game.
The bad news for Williams is that LeSean McCoy is ahead of him on the depth chart. If Shady stays healthy, he won't come off the field much except in goal-line and short-yardage situations. That will limit his productivity.
2017 Bottom Line
Williams is a solid backup, but McCoy is a legit top-5 fantasy back. Williams will not put up any crazy numbers, but his role with the Bills is pretty much set. He is definitely depth, and if he scores touchdowns, he will justify his RB46. He is not worth drafting until the later round as a fourth back, at best.