One of the problems that Leveon Bell had was that he has such an unorthodox running style, even when he was in his salad days in Pittsburgh. He get the handoff, dance around in the backfield for longer than any RB, wait for a hole to develop, and then accelerate. When he was younger, it lead to some longer runs, but set him up to lose yardage or gain less than what was blocked in other cases.
He was, in some ways, a very poor man's version of Barry Sanders. Sanders danced around a lot too, ran horizontally, and had a lot of carries for lost yardage (for example, the infamous 13 carry, -1 yard game against the Packers in the playoffs).
https://gameonwi.com/green-bay...ory-shurmur-sanders/
It often worked for Sanders because he would go something like 7-8 carries for almost nothing and then break a home run on the next carry more often than almost any RB in history. Bell as a Steeler broke some long ones, but when he lost that burst he became almost worthless. You can give Adrian Peterson the ball on a day's worth of preparation and he'll get what's blocked. Leveon Bell is not that kind of back.