REF - Remove unneeded return from private fn, add comments

[colemanw]

Overview

Simple code cleanup & add comments.

[civibot]

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[eileenmcnaughton]

This seems fine but we can also remove another return in the same function

[colemanw]

@eileenmcnaughton actually that return is not from the same function, it's from a nested callback to addSettingsFactory

[eileenmcnaughton]

Oh yuck - a nested call back - OK merging