I have to agree. Don't have either and crave the 200L, but...have rented the 135 and 85L on different occasions. Both have learning curves, but the 85L got me some amazing shots, whereas the 135...so so. Each time shot em with 5DMkII, each time on a monopod. Got better shots in action without the monopod using the 85L than I did with the 135 on a monopod. Wedding use each time. So I have to agree with the OP that I wasn't as impressed with the 135L as I was with the 85L, price not being a determining factor.
Also, while the Sigma 85 might have been a bit faster focusing, the Canon 85L took better pictures. Sent the Sigma back. Loved it stopped down, but I didn't buy it to use stopped down!
I've seen a lot of very nice pictures taken with the 135L. And I'm sure I'd get a lot of pictures I would love if I got that lens. But I'm finding my 100L Macro impresses me too and get's the ring shots as well. So I don't think I'll be getting the 135.
It's always about how you shoot, what you shoot, and how you use it. So very seldom does one persons Grand Slam answer serve the other persons interest. Simple, and as complicated, as that.
I also really like the 100 macro. Almost bought one. Don't shoot that much macro or copy work so I rent when I need one but if I shot more of those kinds of things I would have one.