Thanks Ness. So, I guess "Principals with CONTROL permission on a securable can grant permission on that securable.

Grantees of CONTROL permission on a schema can grant any permission on any object within the schema" means that principals can ONLY grant permissions on securables but not access the securable, for example, with a Select, Insert, Delete or Update Statement. Hence, the reason for having to apply the individual permissions for Select, Insert, Delete and Update Statements:

GRANT SELECT ON SCHEMA::[Developer_Schema] TO [Developer_Role]

GO

GRANT INSERT ON SCHEMA::[Developer_Schema] TO [Developer_Role]

GO

GRANT DELETE ON SCHEMA::[Developer_Schema] TO [Developer_Role]

GO

GRANT UPDATE ON SCHEMA::[Developer_Schema] TO [Developer_Role]

GO

I will have to read up more on this topic.

Thanks, Kevin