Cutler has struggled for the Bears in recent seasons with fitness issues and talent in the receiver positions stopping his side from reaching their potential.
"I think Jay Cutler is probably learning things about the quarterback position that he has never had mentioned to him in his life," Simms told reporters.
"So is that important? You're right, it is. It's very important. You take somebody with his talent and you tweak it a little, you get greatness.
"You could coach somebody else and coach them enough to be their greatest, and still have an average player, but Jay Cutler is an extremely talented guy, and there's no doubt he needs to polish his game."
Chicago open their regular season campaign the Cincinnati Bengals on September 8.