re: Why is Jo-Lonn Dunbar not being given a chance to start at Sam?

He was a undersized MLB (similar to Vilma) coming out of college. I think they like him more than Marvin Mitchell so he's now the #2 MLB. I think last year was his real opportunity to make it at either side OLB. He started at SLB until early Dec. when he went IR with a hammy. He obviously didn't impress enough as evidenced by bringing in so many other LBs.

reviewing his college scouting report-

Undersized but feisty middle linebacker who was the leader of a very good Boston College defense this past season, who was was named a team captain when only a junior and a first-time starter, indicating how much his teammates thought of the defender.

As a senior, Dunbar was a major part of a unit which led the country at stopping the run for most of last year’s campaign. His stature, at 6 feet even and 231 pounds, belies the toughness with which he approaches the game. It should be noted that some of his size limitations were hidden due to the fact the Golden Eagles had monstrous run stuffers protecting their middle linebacker over the past two seasons.

During his career at Boston College, Dunbar's production outmatched potential with 269 total tackles in 25 career starts. Injuries were an issue, as he was never able to complete an entire season as a starter. For example, an ankle injury hampered his play for a stretch of his senior campaign.

Athletically, Dunbar does not automatically jump off the screen. His overall speed and agility are average, posting forty yard dash times in the high 4.8’s, as well as a 4.45 short shuttle and 7.05 three cone drill. Dunbar numbers might not leap off the page, nor is he the most physically talented player on the field at any given time, but he is a natural athlete - this is a linebacker who was recruited as a running back.

Dunbar could be a special player: a linebacker which displayed a nose for the ball leading to four touchdowns throughout his defensive career, a playmaker who relied on his instincts, attitude, and guts to get the job done.

Good enough for NFL teams to give him a look at a late round prospect.