Allegedly, on or about 19 March 2017, François Patte sent:
My last attempt to install f25 was done creating /, /boot, /usr, /var, /home, /opt and swap partitions on RAID1 devices and *yes* anaconda accepted that *but* I can't log-in because all the passwords I gave are not recognized and I don't know why at this time, so I can't tell you what is the system configuration right now.
As I recall, Fedora (or upstream) broke having /usr as a separate partition many years ago. Something about the tools used to mount things are (now) inside it, so it needs to be already there at boot time, if I recall correctly.
I don't know about your partitioning issues, but *this* will have its own problems. It's possibly the cause of your inability to log in (such login tools probably inside an unmounted /usr partition).