Apache 2.0 and GPL compatibility

[Bob Scheifler]

In a March 2003 discussion on this list about whether the AFL was or
wasn't GPL compatible, it seemed that a key point was that, because
the AFL does not grant the right to sublicense, the AFL applies to
any parts of an original work that remain in a derivative work, even
if the derivative work as a whole is under a different license.

The Apache License version 2.0 does grant the right to sublicense,
as I understand it. Was that factored into the analysis given here:
     http://www.apache.org/licenses/GPL-compatibility.html
? If the right to sublicense means no part of the derivative work
needs to remain under the original license, then why would granting
or revoking a patent license for the original work have any effect on
implicit patent rights for the derivative work?

- Bob [risking the wrath of the gods]