Hartline doesn't suit this system and will see his production decline further, imo. I hate his lack of toughness after the catch and he would be a depth guy on a lot of rosters. May of us said it before the season that when the sideline comeback routes dry up, Hartline will dry up with them. I think that's been borne out.
Matthews isn't the second coming, by any means, but he had a very productive day Sunday, not just with the TD but in special teams also, where he really stood out to me for his effort and hustle. That didn't indicate a guy lacking application. I don't know why he isn't trusted more in the offense. It would seem to suit him well.
Could be that Matthews gets snaps that were Gibson's rather than at Hartline's expense. That would annoy me though. A guy like Jax's Hurns, a UDFA who ran a 4.55 at the Combine, can get separation at will and get YAC despite a slender frame, but Hartline with similar speed and size can't separate and can't stay on his feet. Guys with Hartline's ability just aren't rare, however you spin it.