Methods to get accessors related to is_many accessor

This extracts the name resolution for property names related to is_many accessors.  With these, you can ask the class object what the iterator accessor is for a given is_many property name.
Should the "Returns a false value..." lines be consistently separated or joined together with the preceding description of the methods?  The first one is the only one that is, although its description is also the longest.

I advocate either removing the comma between "is_many, or" or adding a pronoun after the "or" so that the latter portion of the sentence could stand on its own.