I started playing around with the autofocus micro adjustment setting on my camera. The first lens I tried it on was my 50mm 1.2L, I always thought it wasn't sharp enough for an L lens. I don't know if I have gotten the setting perfect yet (currently at +2) but it is definitely much better!
5dm2, 50mm 1.2L, ISO 4000, f/1.2 ss 1/200
I will post a full review of that function and the resources I used after I play with it more.