I watched a lot of him in college, and don't remember him being just so-so on his get-off. I really wanted the Rams to draft him. Since he his has been in the pros, I hadn't watched a lot of him. From what I have seen recenly, he doesn't seem to have much pop off the line of scrimmage. So, it would seem to make sense that his opportunity to get targets stems from running crisp routes, double moves, and knowing when to make cuts. It goes to reason that these things will take time for him so synch with Goff.
Quite frankly, it's been eight weeks now....and the offense was clicking in the first four weeks....so you would think they woul have the opportunity to focus practice time on getting Goff/Sammy in lock step. If Sammy isn't producing the week after the bye......your gonna need start wondering if it will ever happen.
