Some ideas on when a COPE should be used, vs an addition to GOLD
itself:
GOLD consists of 3 types: class, property/relation, and instance.
A COPE should be constructed when a particular project or community
of practice requires a class, property or instance that probably won't
be used by other projects or communities, e.g., ArabicNumberalGender
instances would be an example.
There should be an addition when some entity that would clearly
pertain to many projects is missing, eg. Infinitive, as Damir's
groups pointed out.
A COPE should be a separate file that imports GOLD, using its URI:
http://purl.org/linguistics/gold