I don't think it's redundant at all. At one time (film daze), my kit was built around 20-35-85-135. Then I ended up getting a 200 f2.8 and a 300 f4 (I was newspaper photographer and needed extra reach). This was in the FD lens days, so it was all manual focus.
The 135 L is a great lens. It depends a little on what you photograph though. I wouldn't dismiss the 200mm f2.8 out of hand. (Now my kit is built around 24 L, 50 L, 100 f2 and 200mm f2.8.) The 135 is a little sharper, but the 200 has extra reach and is a little less expensive. If you're photographing youth outdoor sports (baseball, football, soccer etc) the 200 might be a better choice. If you're photographing indoor sports (gymnastics, basketball) the 135 might be better. If you're photographing around the house, you need a really big room to use either.
I second what others have said about the 70-200 f2.8 L. It's so big and heavy that you may find yourself leaving it behind a lot. The 85 + either the 135 or 200 both are more portable (IMO) than the zoom. The 200 (I really like the 200) is amazingly lightweight and sharp and is a great value.
jack