Thanks for such a thorough systematic test, Guy. I am surprised (and pleased to know) just how much sharper the 2/35 gets at f2.8.
I wax hot and cold about getting the 16-35. I already own the Loxia 2/35 (my review is here) which is now my number one lens and the 24-70 which for me performs better than expected. I also use an Ultron 21/1.8 which is fantastic on all alpha cameras and the Heliar 15/4.5 which has problems (not sure if the V3 is that much better in the samples I have seen).
The reason why I would like a 16-35 is that I want to be able to mount filters and the integrated lens hoods on the 21 and 15 prevent this.
However, I think it will be worth hanging in there to see if Zeiss will introduce a Loxia 21 or 18 (to mirror the ZM product line). For me that would be the best solution.
Thanks again, for an interesting comparison test.