Per http://clojure.org/datatypes: "You should always program to protocols or interfaces -
datatypes cannot expose methods not in their protocols or interfaces"
Along those lines, usually for deftypes, I gen an interface with the proper types if necessary, then have the deftype implement the interface to expose the field.
Also per http://clojure.org/datatypes:
"note that currently a type hint of a non-primitive type will not be used to constrain the field type nor the constructor arg, but will be used to optimize its use in the class methods" - that is, inside a method implemented on the record/type, referring to the field should have the right hint. So in the example above, if unwrap was an interface or protocol implementation method on the record, and you referred to the field, you should expect the hint to be utilized in that scenario.
So, my contention would be that all of the behavior described in this ticket should be expected based on the design, which is why I've reclassified this as an enhancement, not a defect.