I figured I would mention that I also experience this problem and drive a 2013. Not sure if they changed anything since I know very little about these cars. I've driven a range of different cars and have never experienced the amount of slip in the rear as I do with this one. I'm sure I am pushing it to hard on the corners but figured this car could handle it. I know that when it rains I have to nearly let off the gas when turning haha.
I'll also admit that I'm sure I would benefit a ton from a driving class.
Maybe I can find one in Dallas this summer.