BlueSpire/Durandal — pull request #579 by drumboog (2014-09-19 14:54:34+00:00)
Title: Delete property before assigning wrapping computed observable.

When Durandal wraps a property with a setter, the new computed observable is assigned to the property, which in turn calls the original setter and passes in the computed observable. Deleting the original property allows the new value to be assigned without invoking the setter.