I presented An Introduction to Configuration Management at the first-ever Flyover Camp in Kansas City, MO. Below is an Apple keynote file and PDF with presenter notes as reference.
Flyover 2019 D8 config management copy.key
Flyover 2019 D8 config management copy.pdf
config_override_warn - If config is overridden in settings.php it will let you know if you try to change it in the UI.
config_readonly - Adds settings.php config to lock down config changes from the UI.
config_split - Alternate config for specific environments