That's what I was afraid of was going to be the only option. Oh well, thanks for the input. They always break one thing and fix another...

Before v1607, I used the gpedit logon script to disable the automatic login of non-passworded accounts. It's been fine for all the time I've been with Win10 since release.
Specifically:

Name:...

I've only seen that report from tablet users. For desktop, I haven't seen anything yet that works.

If you have any other drives with any other versions of Windows on them that can boot, disable them as well via your BIOS. For some reason that's what fixed it for me.

Personally, it was the fact that I have a second boot drive. In particular, one of my other drives has 8.1 on it. The moment I disabled the drive to install the update, it went without a hitch.