“Use iCloud Password” Mac Login Option Removed
Starting in OS X Yosemite, Apple introduced a new option to log into your Mac using the password associated with an Apple ID. As of OS X 10.11.4, this option seems to have been removed from the Users & Groups preference pane in System Preferences.
Curiouser and curiouser. Has Apple removed the option for security reasons? Is there a bug? Why is Apple always so damned secretive?