[Greylist-users] Skipping greylisting based on SPF?

[Steven Grimm]

What do people think of the idea of skipping the greylist process for
mail where the remote IP address is explicitly allowed by the sender
domain's SPF record? In that case you can be reasonably well assured
that the sender domain isn't a forgery, and it's likely that the sending
host is a real mail server that would retry the message.

This would reduce the problem of extended delays for mail from large
ISPs whose retries come from different IP addresses. And it would cut
down on the number of delayed messages in general while probably not
reducing the effectiveness of greylisting overall (since the only hosts
you'd let through would be the ones that are most likely to try again.)

-Steve