SYSML16 — BoundReference constraint#3 is unclear

BoundReference constraint#3 states the following:

The role of boundEnd shall be a property accessible by navigation from instances of the block owning the property to which BoundReference is applied, but shall not be the property to which BoundReference is applied, or one that it is related to by redefinition.

It's not clear what "navigable" means here. Please clarify.

Merged with SYSML16-274

Clarify as suggested as part of SYSML16-311.
Revised text:

self.base_Property.association->notEmpty() and 
self.boundEnd.definingEnd->notEmpty() and
self.base_Property.association.navigableOwnedEnd->includes(self.boundEnd.definingEnd)