Hello ethandron,...
Never mix the two together.
Freshly cooked spaghetti,drained,(add a little of the cooking water),a sprinkling of olive oil.Toss to incorporate,
Serve roughly 100 grammes per person,and top with just enough ragu to just about coat the pasta ,without making it wet.
Parmesan on the side,along with olive oil,and a black pepper mill.
This may have been a halfway serious question,but this is a serious answer.Despite my user name,I'm VERY Italian,and this stuff is important to me.