
that Salah is world class. He's scored and assists this much because he has no responsibility to track back in Roma's unbalanced attacking-dominant team.
Cuadrado also scored 15 goals-11 assists in 2013-14 when he played in a similarly attacking set up for Viola with no defensive responsibilities. Even Gervinho looked like a class attacker in garcia's attacking system.
Add in the responsibility to track back and aid defensively and all these sorts of players see their production take a swan-dive. But they add more to a team even so, because none of these guys have the ability to put up Neymar, Messi, Ronaldo, etc numbers so it isn't worth it to unbalance your team so much. It makes you too vulnerable to counters on the wing. Hence the reason Roma conceded 3 goals to an atrocious Chievo.