defense is more coaching, offenses is more players, for example offenses need a good QB, there is no way especially in the NFL to scheme around having a shitty QB.
Defense on the other hand you can have average players all around and still scheme yourself to a top 10 maybe even 5 defense with the right coach.
I have to agree with this sentiment. The first thing an offense needs is an elite QB. Not mediocre or average but elite. There are 32 teams and I guarantee not all have elite QB's. Carolina is lucky because I believe Cam is on his way there. He is not there yet but on his way. What I am saying is that it is a mixture on offense between coach and QB. Coaching can help with development but it can also get that coach fired ie. Jay Cutler in Chicago and Denver. The QB also has to have a drive to want to improve and be considered great.