cfengine failover on copy does not seem to work as documented

[Nielsen, Steve]

I am trying to use failover to define a class when the copy fails in
some way.

The documentation indicates that the failover class is activated on a
copy error (no matter what kind error):

from the docs:
===================
failover
    If a file copy fails due to an error, the classes in this assignment
will become active, allowing failover rules to become active.
==================

However on testing this out the failover class only gets activated when
remote server cannot be reached.  Otherwise failover is not activated.

I would think any of these errors should also trigger the failover
class:

* server is up but file not found
* copy is local but file not found

Comments ?

Steve