And a later back..... + backs onwards i think.
however ... in the real world syncing at 1/800th is fast and having this ability solves a lot of problems....
If you shoot in a hot country after 9:30 am (weddings or interiors) then 1/1600 might be needed...
I just think we are lucky to have not one but two specialist manufacturers providing us with these terrific lenses.
Hassy V and Bronica and Rollei were 1/500th not that long ago.
S