If not signed, the question becomes whether Peterson would be the next option. Offensive coordinator Darrell Bevell worked with Peterson in Minnesota, so the familiarity is there.
Seattle’s running game badly missed Marshawn Lynch in 2016, following his mid-Super Bowl 50 retirement. Charles, if healthy, bring an element of excitement that has been missing since Lynch left.
The real question is whether Charles is healthy. He tore an ACL in 2015 and never was fully healthy in 2016, appearing in three games and carrying the ball only 12 times.
At his best, Charles can average well over five yards per carry on a consistent basis (his career average is 5.5), and he can catch plenty of passes. In 2013 alone, he had 70 receptions.