Yes, I know there are plenty of times watching him in real time where it seems like he struggles with finishing through contact. But the picture you are trying to paint is way, way off base. Suggesting that DD has something to learn from Ross in this category seems a little much when Ross had one of the lowest free throw rates in the entire league last season. I mean like ten from the bottom of all qualifying players bad. He had a few highlight reel dunks during the middle of the season but mainly floated around the perimeter offensively during his rookie year.
And I'm not even really a DeRozan fan. There are plenty parts to his game that can be criticized. I do think he's grown into a very aggressive player on O however.