Goodrow was very much a 4th liner coming into the season.
The Sharks were winning games when the top line was Hertl-Goodrow-Meier.
Obviously, Hertl was the reason that line was successful, but Goodrow didn't ruin it, or anything.
He is currently a 3rd line winger for one of the best teams in the league.
But, that isn't really my point. All I am saying is players can get better, even after 25 years old. With Kellman, I feel like there are things he does that really push the play up the ice, and control the puck, he just doesn't do them enough to be more than a 4th line guy. Consistency is absolutely something that gets better with NHL experience.